EXHIBIT 10.4

               SECOND AMENDED AND RESTATED LIQUIDITY UNDERTAKING

      This Second Amended and Restated Liquidity Undertaking (this "Agreement"),
dated  effective  as of January  31,  1997,  is  executed  and  delivered  by NL
INDUSTRIES,  INC., a New Jersey corporation ("NL Industries"),  KRONOS,  INC., a
Delaware  corporation  f/k/a Kronos (USA),  Inc.  ("Kronos")  (NL Industries and
Kronos  are  sometimes  hereinafter  individually  called  a  "Shareholder"  and
collectively called  "Shareholders") and KRONOS INTERNATIONAL,  INC., a Delaware
corporation  ("Borrower")  to  and  in  favor  of  HYPOBANK  INTERNATIONAL  S.A.
("Agent"), as Agent for the Banks (hereinafter defined), and the Banks.

                                  WITNESSETH:

      Borrower,  Kronos  Titan-GmbH,  Agent  and  the  Banks  are,  concurrently
herewith,  entering into that certain Second Amended and Restated Loan Agreement
dated as of January  31, 1997 (as the same may be amended or  supplemented  from
time to time now or  hereafter,  the "Loan  Agreement"),  which  Loan  Agreement
amends and restates that certain Amended and Restated Loan Agreement dated as of
October  15,  1993,  among  Borrower,   Agent,   Banque  Paribas,   as  Co-Agent
("Co-Agent"),  and the Banks (or their  precedessors  in  interest)  (the "First
Restated  Agreement"),  which First Restated  Agreement amends and restates that
certain Loan Agreement dated as of May 30, 1990, among Borrower, Agent, Co-Agent
and the Banks (or their  predecessors  in interest),  as amended by that certain
(i) First  Amendment  Agreement  dated as of  December  31,  1990,  (ii)  Second
Amendment  Agreement  dated as of March  22,  1991,  and (iii)  Third  Amendment
Agreement  (herein   so-called)  dated  as  of  June  15,  1992  (the  "Original
Agreement").

      Pursuant to the Third  Amendment  Agreement,  the parties hereto  executed
that  certain  Liquidity  Undertaking  dated as of June 15, 1992 (the  "Original
Liquidity  Undertaking").  Pursuant to the First Restated Agreement, the parties
hereto executed that certain Amended and Restated Liquidity Undertaking dated as
of October 15, 1993 (the "First Restated Liquidity  Undertaking")  which amended
and restated the Original  Liquidity  Undertaking.  In order to induce Agent and
the Banks to enter into the Loan Agreement,  Shareholders and Borrower desire to
amend and restate the First Restated Liquidity Undertaking as herein set forth.

      NOW,  THEREFORE,  for and in consideration of the Loan Agreement and other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged,  the parties hereto hereby agree that the First Restated Liquidity
Undertaking is amended and restated in its entirety as follows:

      i.    Definitions.  Unless otherwise defined in this Agreement,  initially
            capitalized  terms used in this  Agreement  shall have the  meanings
            ascribed to them in the Loan  Agreement.  As used in this Agreement,
            the phrase  "any  Shareholder"  means any  Shareholder  and/or  both
            Shareholders.

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      ii.         Maintenance of Liquidity.

                        (i)   Liquidity Report. By 5:00 p.m. (New York, New York
                              time) on each  Business Day (i) which occurs prior
                              to  January  1,  2001 and (ii)  which is the first
                              Business Day  immediately  preceding any date upon
                              which  Borrower is required to make any payment of
                              principal  or  interest  on the  Loans  (any  such
                              Business  Day herein a "Report  Date" and any such
                              date upon which  Borrower  is required to make any
                              such payment  hereinafter called a "Payment Date")
                              but  excluding  any day upon which the  payment of
                              principal  on the Loan is due as a  result  of the
                              acceleration  thereof,  Borrower agrees to provide
                              Shareholders   and  Agent   with  a  report   (the
                              "Liquidity   Report")    identifying    Borrower's
                              Liquidity Level as of the prior Business Day (each
                              such  prior   Business   Day  herein  a  "Date  of
                              Determination") and showing, in reasonable detail,
                              Borrower's Liquidity Level and the manner in which
                              such  Liquidity  Level  was  calculated.  As  used
                              herein,  the term  "Liquidity  Level" means, as of
                              each  Date  of   Determination   the  sum  of  (i)
                              Borrower's   Cash  Position,   plus  (ii)  without
                              duplication,  each Consolidated Subsidiaries' Cash
                              Position,  plus (iii) if no Default has  occurred,
                              the amount  available  to be  borrowed by Borrower
                              under  the  terms  of  Section  2.04  of the  Loan
                              Agreement but  excluding any amounts  available to
                              be  borrowed by  Borrower  under any other  credit
                              facilities,  minus  (iv)  the  amount  of all  the
                              payments  scheduled  to be made under the Loans on
                              the Payment Date immediately  following the Report
                              Date.  As used  herein,  the term "Cash  Position"
                              means,  with  respect to any  Person,  the amount,
                              expressed in Deutsche Mark, equal to the remainder
                              of (A) the  sum of such  Person's  cash  and  cash
                              equivalents  (determined in accordance with German
                              GAAP with respect to Borrower and its Consolidated
                              Subsidiaries  or determined  on an  unconsolidated
                              basis but otherwise in accordance  with accounting
                              principles generally accepted in the United States
                              ["U.S.  GAAP"] with  respect to the  Shareholders,
                              both  consistently  applied) plus the market value
                              of such Person's  Marketable  Securities minus (B)
                              without  duplication,  the aggregate amount of any
                              Indebtedness  secured  by any Lien,  other  than a
                              Lien in favor of Agent as security  for the Loans,
                              affecting  such  cash,  cash  equivalents   and/or
                              Marketable  Securities (in each case not to exceed
                              the amount

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                              or value of the particular  cash, cash equivalents
                              or Marketable  Securities  affected by such Lien).
                              As used herein,  the term "Marketable  Securities"
                              means all stocks, bonds, notes or other securities
                              which  are  regularly  traded  on  any  recognized
                              national or  international  market or exchange and
                              are  otherwise  freely  transferable.  The  market
                              value of Marketable Securities shall be determined
                              as of each Date of Determination by reference to a
                              market   price   quoted  as  of  such  date  in  a
                              recognized  national  or  international  market or
                              exchange for the Marketable Securities in question
                              and otherwise on a basis  reasonably  satisfactory
                              to  the  Majority   Banks.   If  any  cash,   cash
                              equivalent or the value of  Marketable  Securities
                              is denominated in any currency other than Deutsche
                              Mark,  then, for purposes of calculating  the Cash
                              Position  under  this  Agreement,  the  equivalent
                              amount of  Deutsche  Mark shall be  determined  by
                              using the Spot Rate existing as of the  applicable
                              Date of Determination.  As used in this Agreement,
                              the term "Spot Rate", with respect to any currency
                              and any day,  means the rate  determined  based on
                              the "Frankfurt  Foreign  Exchange  Fixing" for the
                              offered rates to purchase  Deutsche Mark with such
                              currency as reflected on the display designated as
                              page "1011" on the Telerate Systems,  Incorporated
                              service  (or such other page as may  replace  page
                              "1011"  on  that   service  for  the  purposes  of
                              displaying  such offered  rates) at or about 11:00
                              a.m.  London  time on such  date.  If at least two
                              such  offered  rates appear on such  display,  the
                              rate for such date will be the arithmetic  mean of
                              such offered rates.

                        (ii)  Borrower Liquidity Deficit;  Required  Investment.
                              If  Borrower's  Liquidity  Level  is less  than DM
                              25,000,000  (Deutsche Mark Twenty Five Million) as
                              of any Date of Determination,  Shareholders  shall
                              on a joint, several, irrevocable and unconditional
                              basis  (but  subject to  subparagraph  (d) of this
                              Paragraph  2),  within ten (10) days  after  being
                              given the applicable  Liquidity Report (or if such
                              Liquidity Report is not delivered, within ten (10)
                              days after being given written  notice from Agent)
                              either  make  Capital  Contributions  to  Borrower
                              and/or make  Subordinated  Loans to  Borrower,  in
                              either case in an aggregate  amount  sufficient so
                              that,  after giving  effect to such  contributions
                              and/or such loans and the receipt of such funds by
                              Borrower,  Borrower's  Liquidity Level (calculated
                              as if such contributions and/or

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                              loans  were  made  as of the  applicable  Date  of
                              Determination) shall equal or exceed DM 25,000,000
                              (Deutsche Mark Twenty Five Million); provided that
                              the aggregate amount of Capital  Contributions and
                              Subordinated   Loans  made  by   Shareholders   to
                              Borrower  after  January  31,  1997  and  prior to
                              January 1, 2001 pursuant to this  Agreement  shall
                              not  exceed  an  aggregate   amount  equal  to  DM
                              125,000,000 (Deutsche Mark One Hundred Twenty-Five
                              Million)   (the   "Maximum   Required   Investment
                              Amount");  and provided further that Shareholders'
                              obligations to make Capital  Contributions  and/or
                              Subordinated  Loans  up to  the  Maximum  Required
                              Investment Amount shall be satisfied by any of the
                              following:  (A) to  the  extent  and in an  amount
                              equal  to,  as of the date of  determination,  the
                              positive  remainder  (if any) of (1) the aggregate
                              amount   of    Shareholders'    optional   Capital
                              Contributions  and/or  Subordinated  Loans made to
                              Borrower   after  January  31,  1997  for  general
                              corporate purposes (including, without limitation,
                              optional  prepayments)  minus  (2)  the sum of the
                              aggregate  amount of  Restricted  Payments made by
                              Borrower  prior to the date of  determination  but
                              after   January  31,  1997   pursuant  to  Section
                              16.20(b) of the Loan  Agreement plus the aggregate
                              amount of Restricted Payments permitted (as of the
                              date of  determination)  to be made by Borrower on
                              or after  the date of  determination  pursuant  to
                              Section 16.20(b) of the Loan Agreement, and (B) an
                              amount equal to the Liquidity  Undertaking  Credit
                              in  effect  as of the date of  determination.  The
                              term "Capital  Contributions"  means contributions
                              by a  Shareholder  to the equity of Borrower.  The
                              term   "Subordinated   Loans"  means  loans  by  a
                              Shareholder  to Borrower  on terms and  provisions
                              acceptable  to  such   Shareholder  and  Borrower;
                              provided that such loans are "Subordinated  Debt",
                              as such term is defined in the Loan Agreement.

                        (iii) Event    of    Default;    Required    Investment.
                              Notwithstanding anything to the contrary contained
                              elsewhere  in  this  Agreement,  if  an  Event  of
                              Default has occurred and is  continuing  and Agent
                              shall have given Borrower and Shareholders written
                              notice  requesting or requiring  performance under
                              this   subparagraph   (c),   then   Borrower   and
                              Shareholders'   jointly  and  severally  agree  as
                              follows:


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                  (i) a  Liquidity  Report  shall be  provided  by  Borrower  to
            Shareholders  and Agent  within two Business  Days after  Borrower's
            receipt of such notice referred to in this  subparagraph  (c), which
            Liquidity Report shall identify Borrower's Liquidity Level as of the
            Business  Day  immediately  succeeding  the date of such notice (the
            "Default  Date  of  Determination");  provided,  however  that,  for
            purposes of this  subparagraph (c), the term "Liquidity Level" shall
            mean (without  duplication)  (A) the  Liquidity  Level as defined in
            subparagraph (a) of this Paragraph 2 minus, (B) the aggregate unpaid
            principal  amount  of the  Loans,  minus  (C) the  aggregate  of the
            accrued and unpaid  interest and fees under the Loan  Agreement  and
            the other Loan Documents; and

                  (ii)  based  upon  the  Liquidity  Level as so  determined  in
            accordance with clause (i) immediately  preceding,  the Shareholders
            shall, on a joint, several, irrevocable and unconditional basis (but
            subject to  subparagraph  (d) of this  Paragraph 2), within ten (10)
            days after being given such notice from Agent,  either make  Capital
            Contributions  to  Borrower  and/or  make   Subordinated   Loans  to
            Borrower,  in either case in an aggregate amount sufficient so that,
            after giving effect to such contributions  and/or such loans and the
            receipt of such funds by Borrower,  Borrower's  Liquidity  Level (as
            defined  in  this   subparagraph  (c)  and  calculated  as  if  such
            contributions  and/or loans were made as of the  applicable  Default
            Date of Determination) shall equal or exceed DM 25,000,000 (Deutsche
            Mark Twenty Five  Million);  provided that the  aggregate  amount of
            Capital Contributions and Subordinated Loans made by Shareholders to
            Borrower  after  January  31,  1997 and  prior to  January  1,  2001
            pursuant to this  Agreement  shall not exceed the  Maximum  Required
            Investment Amount. Notwithstanding anything to the contrary that may
            be contained in this Agreement,  payments by NL Industries under the
            NL Guaranty will not reduce or otherwise affect the Maximum Required
            Investment Amount.

                        (iv)  Priority of Contributions  by  Shareholders.  Each
                              time the Shareholders are required to make Capital
                              Contributions or Subordinated Loans (the "Required
                              Contributions")  under subparagraphs (b) or (c) of
                              this  Paragraph  2, Kronos  shall be  obligated to
                              make so much of the Required  Contributions  as it
                              is  able  to  make  from  funds  received  from or
                              otherwise attributable to its operations before NL
                              Industries  (i) makes any portion of the  Required
                              Contributions or (ii) contributes  funds to Kronos
                              to   enable    Kronos   to   make   the   Required
                              Contributions.  Kronos  agrees  that it  will  not
                              utilize any funds  received  from NL Industries to
                              make  any  Required  Contributions  until  it  has
                              utilized  all the then  available  funds which are
                              received  from or  otherwise  attributable  to its
                              operations.   After  Kronos  has   satisfied   its
                              obligations under the preceding two sentences or

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                              if   Kronos    is   unable   to   make    Required
                              Contributions,   then  NL   Industries   will,  if
                              necessary,  promptly  (within  the  ten  (10)  day
                              period  specified  in  subparagraph  (c)  of  this
                              Paragraph  2) make the Required  Contributions  or
                              the remainder thereof left unpaid.

                        (v)   Payments. All payments by either Shareholder under
                              this Agreement  shall be in immediately  available
                              funds  and made  directly  to  Borrower's  account
                              number   5803610284   maintained   at   Bayerische
                              Hypotheken-und  Wechselbank AG in Munich, Germany.
                              All payments by the  Shareholders  hereunder shall
                              be made without setoff,  deduction or counterclaim
                              for amounts owed to any  Shareholder  by Borrower.
                              Each  Shareholder   irrevocably   waives,  to  the
                              fullest  extent  permitted by law,  all  defenses,
                              rights of setoff and counterclaims,  which may now
                              exist or  hereafter  arise  with  respect  to such
                              payments   or   other   obligations   under   this
                              Agreement.  All payments by each Shareholder under
                              this  Agreement  shall also be made free and clear
                              of, and without withholding or deduction for or on
                              account  of, any  present  or future  taxes now or
                              hereafter  imposed on  Borrower  or its  property,
                              except  to the  extent  that such  withholding  or
                              deduction is required by applicable law.

                        (vi)  Borrower Obligations.  Borrower hereby irrevocably
                              and unconditionally agrees to either (i) authorize
                              (to the extent necessary),  issue and sell capital
                              stock  to  Shareholders,  in  connection  with any
                              Capital Contributions, or (ii) authorize and issue
                              promissory notes and any other necessary documents
                              to evidence the  Subordinated  Loans or (iii) take
                              such other action at such time as is necessary for
                              Shareholders to comply with the provisions of this
                              Paragraph 2. Neither the  obligations  of Borrower
                              under this  subparagraph  (f), any other provision
                              of this  Agreement or any other Loan  Document nor
                              the  performance  thereof  shall be a condition to
                              the obligations of Shareholders to pay to Borrower
                              the  amounts   required   under  this   Agreement;
                              provided  that  either  Shareholder's  performance
                              shall  not  constitute  a  waiver  of  any  rights
                              against Borrower.

                        (vii) Termination. The obligations of Shareholders under
                              this  Paragraph  2 shall  terminate  on January 1,
                              2001 (the "Termination  Date") except with respect
                              to any  obligation  under this  Paragraph  2 which
                              remains unsatisfied on the

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                              Termination   Date  and  except  as   provided  in
                              subparagraph (j) and (k) below.

                        (viii)Failure to Perform; No Proof of Damages;  Specific
                              Performance.   Borrower   and   each   Shareholder
                              recognize and agree that in the event  Borrower or
                              any Shareholder fails to perform or observe any or
                              all of its obligations  under this Agreement,  and
                              if for any  reason  Agent or any Bank  shall  have
                              failed to receive when due and payable (whether at
                              stated maturity,  by  acceleration,  or otherwise)
                              the  payment  of all or any part of  principal  or
                              interest or any other  amount  payable by Borrower
                              under  the  Loan   Agreement  or  the  other  Loan
                              Documents,  then in each  such  case it  shall  be
                              assumed  conclusively  without  necessity of proof
                              that such failure by Borrower or Shareholders  was
                              the  sole  and  direct  cause of Agent or any Bank
                              failing  to   receive   such   payment   when  due
                              irrespective   of  any   other   contributing   or
                              intervening cause  whatsoever.  As a result of the
                              forgoing,  Shareholders  and Borrower  irrevocably
                              waive to the full extent  permitted by  applicable
                              law  any  right  or  defense   that   Borrower  or
                              Shareholders  may have to cause  Agent or any Bank
                              to prove the cause or amount of any  damages or to
                              mitigate  the  same.  In  addition,   and  without
                              limiting the  forgoing,  the parties  hereto agree
                              that in the  event  of such a  failure,  (i) it is
                              impossible  to measure in money the  damages  that
                              would be  suffered  by Agent and the  Banks,  (ii)
                              Agent and the Banks  will be  irreparably  damaged
                              and  (iii) any  remedy  at law will be  inadequate
                              relief and, as a result,  this Agreement  shall be
                              enforceable  by Agent  and the Banks in a court of
                              equity by a decree of specific performance without
                              the  need  of  proving  that  a  remedy  at law is
                              inadequate,  Borrower and each Shareholder  hereby
                              waiving and agreeing not to raise the defense that
                              an adequate remedy at law exists.

                        (ix)  Non-impairment  of Obligations  upon Bankruptcy of
                              Borrower.  The obligations of  Shareholders  under
                              this  Agreement  shall not be released,  impaired,
                              limited, reduced, discharged or otherwise affected
                              on   account   of  the   insolvency,   bankruptcy,
                              arrangement,     adjustment,     composi     tion,
                              liquidation,  disability,  dissolution  or lack of
                              authority of Borrower or any Shareholder,  whether
                              now   existing  or   hereafter   arising  and,  in
                              furtherance  of the  foregoing,  each  Shareholder
                              waives, to the fullest extent permitted by

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                              applicable  law and for the  benefit  of, and as a
                              separate  undertaking  with,  Agent and the Banks,
                              any defense to the  performance  of this Agreement
                              which may be available to either  Shareholder as a
                              consequence  of Borrower not being in existence or
                              this  Agreement  being  rejected or otherwise  not
                              assumed  by  Borrower  or  any  trustee  or  other
                              similar   official   for   Borrower   or  for  any
                              substantial  part of the property of Borrower,  or
                              as a consequence of this Agreement being otherwise
                              terminated  or  modified,  in  any  bankruptcy  or
                              insolvency   proceeding  whether  such  rejection,
                              non-assumption,  termination or modification be by
                              reason  of  this  Agreement  being  held  to be an
                              executory  contract  or by  reason  of  any  other
                              circumstance;  provided  that,  if  Borrower is no
                              longer in  existence  or this  Agreement  shall be
                              rejected or otherwise  not assumed,  or terminated
                              or  modified,  each  Shareholder  agrees  for  the
                              benefit  of, and as a separate  undertaking  with,
                              Agent and the Banks, that it will unconditionally,
                              jointly and severally pay to Agent an amount equal
                              to each payment  which would  otherwise be payable
                              by  Shareholders  under or in connection with this
                              Agreement to Borrower if this  Agreement  were not
                              so  rejected  or  otherwise  not  assumed  or were
                              otherwise  not so  terminated  or  modified  (such
                              amount to be payable to Agent to be applied to the
                              indebtedness,  liabilities and  obligations  owing
                              under or pursuant to the Loan Documents (the "Loan
                              Obligations"))  and in such event,  Borrower shall
                              comply with its  obligations  under  subparagraphs
                              (f) of  this  Paragraph  2.  Shareholders  further
                              agree   that   their    obligations   under   this
                              subparagraph (i) shall continue to be effective or
                              be   reinstated   (if  a  release,   discharge  or
                              termination has occurred but only to the extent of
                              the amount discharged),  as the case may be, if at
                              any time any payment (or any part of such payment)
                              to  Agent or any Bank  previously  paid by  either
                              Shareholder  under the terms of this  subparagraph
                              (i) is rescinded or must  otherwise be restored or
                              disgorged  by Agent or any  Bank  pursuant  to any
                              bankruptcy,      insolvency,       reorganization,
                              receivership,  liquidation  or other debtor relief
                              granted to any  Shareholder  or its  successors or
                              assigns.  If, pursuant to the foregoing  sentence,
                              the   obligations  of   Shareholders   under  this
                              subparagraph (i) shall continue to be effective or
                              be   reinstated   (if  a  release,   discharge  or
                              termination  has  occurred),  any  prior  release,
                              discharge or termination from

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                              the   terms  of  this   Agreement   given  to  any
                              Shareholder  by Agent or any Bank shall be without
                              effect.

                        (x)   No Effect or Impairment. Each Shareholder consents
                              to and  agrees  that its  obligations  under  this
                              Agreement  will also not be discharged or affected
                              by: (i) any acceptance,  forbearance or release in
                              respect of the rights of Agent or any of the Banks
                              under  the  Loan   Agreement  or  the  other  Loan
                              Documents; (ii) any waiver or release of any right
                              or option  of Agent or any of the Banks  under the
                              terms  of  the  Loan   Agreement   or  other  Loan
                              Documents;  (iii)  any  modification,   extension,
                              renewal  or  amendment  of the  terms  of the Loan
                              Agreement or other Loan  Documents;  (iv) the fact
                              that the Loan Agreement or any other Loan Document
                              shall be  invalid,  illegal or  unenforceable,  in
                              whole or in part, for any reason; or (v) except as
                              otherwise   provided  herein,  any  other  act  or
                              omission  of  any  kind  by  Agent,  any  Bank  or
                              Borrower  or  any  other  circumstance  whatsoever
                              which  might   constitute  a  legal  or  equitable
                              discharge of the Shareholders.

                        (xi)  Liquidity Report; Liquidity Level. Borrower agrees
                              to  provide  to Agent and  Shareholders,  promptly
                              upon  any   request   therefor  by  Agent  or  any
                              Shareholders,  such  information in such detail as
                              Agent or any  Shareholder  may reasonably  request
                              from time to time relating to the determination of
                              the   Liquidity   Level   from   time   to   time.
                              Furthermore,  and notwithstanding  anything to the
                              contrary contained elsewhere in this Agreement, in
                              the event that Borrower  fails to timely provide a
                              Liquidity  Report or an accurate  Liquidity Report
                              in accordance with this Agreement  within five (5)
                              days after being given  written  notice from Agent
                              to do so, then for all purposes of this Agreement,
                              the  Liquidity  Level  as of the  applicable  date
                              shall be  deemed  to be the  Liquidity  Level,  as
                              reasonably  determined  by  Agent  in good  faith,
                              specified  in a  written  notice to  Borrower  and
                              Shareholders.

      iii.  Representations  and Warranties of Shareholders.  In connection with
            this Agreement,  Shareholders hereby jointly and severally represent
            and  warrant to Agent and the Banks as follows,  provided,  however,
            that any  representation  or warranty  contained in this Paragraph 3
            made as to a  particular  Shareholder  shall be deemed  made in this
            Agreement only by such Shareholder:


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                        (i)   NL  Industries is the sole  shareholder  of Kronos
                              and Kronos is the sole  shareholder  of  Borrower,
                              and  Shareholders  have received and will continue
                              to receive a direct and indirect  material benefit
                              from the making of this  Agreement,  the Loans and
                              the transactions  evidenced by and contemplated in
                              the Loan  Agreement and the other Loan  Documents;
                              this  Agreement  is  given  by   Shareholders   in
                              furtherance  of the direct and  indirect  business
                              interests and corporate  purposes of Shareholders,
                              and is  necessary to the  conduct,  promotion  and
                              attainment  of the business of  Shareholders;  and
                              the value of the consideration  received and to be
                              received  by  Shareholders  pursuant  to the  Loan
                              Agreement is reasonably  worth at least as much as
                              the liability and obligation of Shareholders under
                              this Agreement;

                        (ii)  Each  Shareholder is a corporation duly organized,
                              validly  existing and in good  standing  under the
                              laws of the jurisdiction of its  incorporation and
                              has the corporate  power and authority to execute,
                              deliver  and perform  its  obligations  under this
                              Agreement. The execution, delivery and performance
                              by each  Shareholder  of this  Agreement have been
                              duly  authorized  by all  requisite  action on the
                              part of each  Shareholder  and do not and will not
                              violate  or   conflict   with  the   articles   of
                              incorporation  or bylaws of either  Shareholder or
                              any law, rule or  regulation  or any order,  writ,
                              injunction  or decree of any  court,  governmental
                              authority or arbitrator to which such  Shareholder
                              is  subject  and do not and will not result in the
                              creation or imposition of any Lien upon any of the
                              revenues  or  assets of  either  Shareholder.  The
                              execution  and delivery of this  Agreement and the
                              performance  of and  compliance  with the terms of
                              this Agreement will not conflict with,  constitute
                              a default  (or an event which with notice or lapse
                              of time or both would constitute a default) under,
                              or result in the breach of, any material contract,
                              agreement  or  other   instrument   to  which  any
                              Shareholder  is a party or which may be applicable
                              to any Shareholder or any of its assets;

                        (iii) This  Agreement,  when  executed and  delivered by
                              each Shareholder and Borrower, will constitute the
                              joint and  several  and valid,  legal and  binding
                              obligation  of  each  Shareholder  enforceable  in
                              accordance  with its  terms,  except to the extent
                              that enforcement may be limited by

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<PAGE>



                              bankruptcy, insolvency, reorganization, moratorium
                              or other similar laws affecting the enforcement of
                              creditors'  rights  generally and by principles of
                              equity;

                        (iv)  As of the date of this Agreement, and after giving
                              effect  to  this   Agreement  and  the  contingent
                              obligations  evidenced  by  this  Agreement,  each
                              Shareholder is not, and will not be, insolvent (as
                              such  term is used or  defined  in all  applicable
                              bankruptcy,   fraudulent   transfer,   insolvency,
                              fraudulent  conveyance and similar laws), and each
                              Shareholder has and will have assets which, fairly
                              valued,  exceed its indebtedness,  liabilities and
                              obligations;

                        (v)   All corporate acts and  conditions  required to be
                              performed and satisfied prior to the execution and
                              delivery of this Agreement, and to constitute this
                              Agreement  as the valid,  binding and  enforceable
                              obligation of each  Shareholder in accordance with
                              its terms,  except to the extent that  enforcement
                              may  be   limited   by   bankruptcy,   insolvency,
                              reorganization,  moratorium  or other similar laws
                              affecting the  enforcement  of  creditors'  rights
                              generally and by  principles of equity,  have been
                              performed  and  satisfied in  accordance  with all
                              applicable laws;

                        (vi)  Each   Shareholder   is  familiar  with,  and  has
                              independently    reviewed    books   and   records
                              regarding, the financial condition of Borrower and
                              is  familiar   with  the  value  of  any  and  all
                              Collateral  and  other   collateral  and  security
                              intended  to secure or to be created to secure the
                              Loans;   however,  each  of  Shareholders  is  not
                              relying  on  such  financial   condition  or  such
                              Collateral,   collateral   or   security   as   an
                              inducement to enter into this Agreement; and

                        (vii) Except for the execution of the Loan  Agreement by
                              Agent and Majority  Banks,  neither Agent,  any of
                              the  Banks  nor any  other  Person  has  made  any
                              representation,   warranty  or  statement  to,  or
                              promise,   covenant   or   agreement   with,   any
                              Shareholder  in order to  induce  Shareholders  to
                              execute this Agreement.

      iv.   Representations and Warranties of Borrower.  In connection with this
            Agreement,  Borrower hereby represents and warrants to Shareholders,
            Agent and the Banks as follows:


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<PAGE>



                        (i)   Borrower is a corporation duly organized,  validly
                              existing  and in good  standing  under the laws of
                              the  jurisdiction  of its  incorporation,  has all
                              requisite corporate power and authority to own its
                              assets and carry on its  business  as now being or
                              as proposed to be conducted, and has the corporate
                              power  and  authority  to  execute,   deliver  and
                              perform its obligations under this Agreement;

                        (ii)  The   execution,   delivery  and   performance  by
                              Borrower   of  this   Agreement   have  been  duly
                              authorized by all requisite  action on the part of
                              Borrower  and do  not  and  will  not  violate  or
                              conflict  with the  articles of  incorporation  or
                              bylaws of Borrower or any law,  rule or regulation
                              or any order,  writ,  injunction  or decree of any
                              court,  governmental  authority or  arbitrator  to
                              which Borrower is subject, and do not and will not
                              result in the creation or  imposition  of any lien
                              upon any of the  revenues  or assets of  Borrower.
                              The execution  and delivery of this  Agreement and
                              the  performance of and compliance  with the terms
                              of  this   Agreement   will  not  conflict   with,
                              constitute  a  default  (or an  event  which  with
                              notice or lapse of time or both would constitute a
                              default)  under,  or result in the  breach of, any
                              material  contract,  agreement or other instrument
                              to  which  Borrower  is a party  or  which  may be
                              applicable to Borrower or any of its assets;

                        (iii) This  Agreement,  when  executed and  delivered by
                              each Shareholder and Borrower, will constitute the
                              valid,  legal and binding  obligation  of Borrower
                              enforceable in accordance  with its terms,  except
                              to the extent that  enforcement  may be limited by
                              bankruptcy, insolvency, reorganization, moratorium
                              or other similar laws affecting the enforcement of
                              creditors'  rights  generally and by principles of
                              equity; and

                        (iv)  All corporate acts and  conditions  required to be
                              performed and satisfied prior to the execution and
                              delivery of this Agreement, and to constitute this
                              Agreement  as the valid,  binding and  enforceable
                              obligation  of  Borrower  in  accordance  with its
                              terms,  except to the extent that  enforcement may
                              be    limited    by    bankruptcy,     insolvency,
                              reorganization,  moratorium  or other similar laws
                              affecting the  enforcement  of  creditors'  rights
                              generally and by

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<PAGE>



                              principles  of  equity,  have been  performed  and
                              satisfied in accordance with all applicable laws.

      v.    Cumulative Remedies; No Election.  The rights of Agent and the Banks
            under this Agreement shall be cumulative of any and all other rights
            that Agent and the Banks may ever have  against any  Shareholder  or
            Borrower  or  arising  under  the  Loan  Documents,  or at law or in
            equity.  The  exercise  by Agent or any Bank of any  right or remedy
            under this Agreement or under any other Loan Document,  or at law or
            in equity,  shall not preclude the concurrent or subsequent exercise
            of any other right or remedy.  This  Agreement  may be enforced from
            time to time as often as  occasion  therefor  may  arise,  and it is
            agreed  that it shall not be  necessary  for  Agent or any Bank,  in
            order to enforce the provisions of this Agreement, first to exercise
            any rights against Borrower,  any Shareholder or any other Person or
            institute suit or to exhaust any available remedies against security
            in its  possession  or under its control,  or to resort to any other
            sources or means of obtaining  payment of the Loans. The obligations
            and duties of  Shareholders  under this Agreement are independent of
            the  obligations  and duties of Borrower under the Loan Agreement or
            this Agreement,  and a separate action or actions may be brought and
            prosecuted  against  Shareholders  or either of them, on a joint and
            several basis,  whether or not action is brought against Borrower or
            any other Person obligated in respect of the Loan and whether or not
            Borrower is joined in any such action or actions. In furtherance and
            not in limitation of the foregoing, the obligations and duties of NL
            Industries  under this Agreement are  independent of the obligations
            and duties of NL Industries under the NL Guaranty,  payments made by
            NL Industries under the terms of this Agreement will not be credited
            against  payments made or required to be made under the NL Guaranty,
            payments  made by NL  Industries  under the NL Guaranty  will not be
            credited  against payments made or required to be made hereunder and
            the  rights  of  Agent  and  the  Banks  under  this  Agreement  are
            cumulative  of all  rights  Agent and the Banks may have  against NL
            Industries under the NL Guaranty.

      vi.   Binding Effect. This Agreement is for the benefit of Borrower, Agent
            and the Banks, and their successors and assigns, and in the event of
            an assignment by Agent or any Bank,  its  successors or assigns,  of
            the Loans,  or any part of the Loans,  the rights and benefits under
            this  Agreement,  to the  extent  applicable  to  the  indebtedness,
            liabilities  and  obligations so assigned,  may be transferred  with
            such  indebtedness,  liabilities and obligations.  This Agreement is
            binding,  not only upon  Shareholders  and Borrower,  but upon their
            respective  successors and assigns;  provided that neither  Borrower
            nor any  Shareholder  may assign  any of its  rights or  obligations
            hereunder without the prior written consent of the Majority Banks.

      vii.  Right of Setoff.  With respect to all  obligations  of  Shareholders
            hereunder owed to Agent or the Banks, each Shareholder hereby grants
            to Agent and the Banks a right of  setoff  upon any and all  monies,
            securities or other property of

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<PAGE>



            such Shareholder,  and the proceeds therefrom, now or hereafter held
            or  received  by or in  transit to Agent or any Bank from or for the
            account  of such  Shareholder,  whether  for  safekeeping,  custody,
            pledge, transmission, collection or otherwise, and also upon any and
            all deposits  (general or special) and credits of such  Shareholder,
            and any and all  claims  of such  Shareholder  against  Agent or any
            Banks at any time existing.

      viii. Further  Assurances.  Upon the  reasonable  request  of Agent,  each
            Shareholder  will,  at any time and from time to time,  duly execute
            and deliver to Agent any and all such further agreements,  documents
            and instruments,  and supply such additional information,  as may be
            necessary  or  advisable,  in the  reasonable  opinion of Agent,  to
            obtain the full benefits of this Agreement,  provided, however, that
            delivery of such additional  information is subject to receipt of an
            executed  Confidentiality  Agreement  with  respect to  confidential
            information of any Shareholder or any Person Controlled  directly or
            indirectly by such Shareholder.

      ix.   Invalid Provisions. If any provision of this Agreement is held to be
            illegal,  invalid or  unenforceable  under  present  or future  laws
            effective during the term of this Agreement, such provision shall be
            fully  severable,  this Agreement shall be construed and enforced as
            if such  illegal,  invalid  or  unenforceable  provision  had  never
            comprised a part of this Agreement,  and the remaining provisions of
            this  Agreement  shall remain in full force and effect and shall not
            be affected by the illegal, invalid or unenforceable provision or by
            its  severance  from this  Agreement.  Furthermore,  in lieu of such
            illegal,  invalid or  unenforceable  provision  there shall be added
            automatically  as a part of this Agreement a provision as similar in
            terms to such illegal,  invalid or unenforceable provision as may be
            possible and be legal, valid and enforceable.

      x.    Modification  in Writing.  No  modification,  consent,  amendment or
            waiver of any  provision  of this  Agreement,  and no consent to any
            departure  by any  Shareholder  or  Borrower  from the terms of this
            Agreement,  shall be  effective  unless the same shall be in writing
            and signed by the Majority Banks and then shall be effective only in
            the specific  instance and for the specific purpose for which given;
            provided  that no  amendment,  waiver or other  modification  of, or
            consent to any departure from, the provisions of Paragraph 2 of this
            Agreement or this  Paragraph  10 shall be effective  unless the same
            shall  be in  writing  and  signed  by Banks  who hold at least  80%
            (eighty  percent) of the aggregate  unpaid  principal  amount of the
            Loans.

      xi.   No Waiver,  Etc.  No notice to or demand on any  Shareholder  in any
            case  shall,  of itself,  entitle  any  Shareholder  to any other or
            further notice or demand in similar or other circumstances. No delay
            or  omission by Agent or any Bank in  exercising  any power or right
            under  this  Agreement  shall  impair  any such power or right or be
            construed as a waiver thereof or any acquiescence therein, and no

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<PAGE>



            single or partial exercise of any such power or right shall preclude
            other or further exercise thereof or the exercise of any other power
            or right under this Agreement.

      xii.  Expenses.  If any  Shareholder or Borrower  should breach or fail to
            perform any provision of this Agreement,  Shareholders  agree to pay
            to Agent all reasonable  costs and expenses  (including  court costs
            and reasonable attorneys' fees of outside counsel) incurred by Agent
            in the enforcement of this Agreement.

      xiii. APPLICABLE  LAW. THIS  AGREEMENT  SHALL BE GOVERNED BY AND CONSTRUED
            ACCORDING TO THE INTERNAL LAWS OF THE STATE OF NEW YORK.

      xiv.  Notices.  Unless otherwise  specifically provided in this Agreement,
            any notice or other communication  required or permitted to be given
            under  this  Agreement  shall be in  writing  and may be  personally
            served, telefaxed, telecopied, telexed or sent by courier service or
            first  class  prepaid  mail  (airmail  if to an address in a foreign
            country  from the  party  writing)  and shall be deemed to have been
            given  when  delivered  in  person  or  by  courier  service,   upon
            transmission of a telefax,  telecopy or telex or four (4) days after
            deposit in the mail  (registered,  with postage prepaid and properly
            addressed).  For the purposes of this  Agreement,  the  addresses of
            Borrower,  Shareholders  and Agent  (until  fifteen (15) days' prior
            written  notice of a change thereof is delivered as provided in this
            Paragraph  14 ) shall be as set forth below on the  signature  pages
            hereof in the case of Shareholders and Agent and as set forth in the
            Loan Agreement in the case of Borrower.

      xv.   NO ORAL  AGREEMENTS.  THIS AGREEMENT  REPRESENTS THE FINAL AGREEMENT
            AMONG SHAREHOLDERS, BORROWER AND AGENT AND THE BANKS RELATING TO THE
            SUBJECT  MATTER OF THIS  AGREEMENT  AND MAY NOT BE  CONTRADICTED  BY
            EVIDENCE OF PRIOR,  CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF
            SUCH  PARTIES.  THERE ARE NO UNWRITTEN  ORAL  AGREEMENTS  BETWEEN OR
            AMONG SUCH PARTIES.

      xvi.  Joint   and   Several   Obligations,   Etc.   Except   for   certain
            representations  and  warranties  made by only  one of  Shareholders
            pursuant  to  Paragraph  3  of  this  Agreement,   all  obligations,
            covenants,  agreements,  representations  and warranties  under this
            Agreement or contained in this Agreement shall constitute and be the
            joint    and    several    obligations,    covenants,    agreements,
            representations   and  warranties  of  each  Shareholder;   provided
            however,  that in no event shall the amount of Capital Contributions
            or   Subordinated   Loans  made   pursuant  to  this   Agreement  by
            Shareholders  exceed individually or in the aggregate DM 125,000,000
            (Deutsche Mark One Hundred Twenty-Five Million).


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      xvii. Survival. All representations,  warranties, covenants and agreements
            of any  Shareholder or Borrower in this Agreement  shall survive the
            execution of this Agreement.

      xviii.Counterparts.  This  Agreement  may be  executed  in any  number  of
            counterparts, each of which shall constitute an original, but all of
            which  when  taken  together  shall  constitute  one  and  the  same
            Agreement.

      xix.  CONSENT TO  JURISDICTION,  VENUE.  EACH  SHAREHOLDER  REPRESENTS AND
            WARRANTS   THAT  IT  IS  NOT  ENTITLED  TO  IMMUNITY  FROM  JUDICIAL
            PROCEEDINGS  AND  AGREES  THAT,  SHOULD  AGENT OR ANY BANK BRING ANY
            SUIT,  ACTION OR PROCEEDING IN ANY  JURISDICTION  DESCRIBED BELOW TO
            ENFORCE ANY OBLIGATION OR LIABILITY OF SUCH  SHAREHOLDER  UNDER THIS
            AGREEMENT NO IMMUNITY FROM SUCH SUIT,  ACTION OR PROCEEDING  WILL BE
            CLAIMED BY OR ON BEHALF OF SUCH  SHAREHOLDER  OR WITH RESPECT TO ITS
            PROPERTY.  EACH SHAREHOLDER  IRREVOCABLY SUBMITS TO THE JURISDICTION
            OF ANY FEDERAL OR STATE COURT SITTING IN THE CITY OF NEW YORK, STATE
            OF NEW YORK,  OR IN THE CITY OF HOUSTON,  STATE OF TEXAS,  OR IN THE
            CITY OF DALLAS,  STATE OF TEXAS, OVER ANY SUIT, ACTION OR PROCEEDING
            ARISING  OUT OF OR  RELATING  TO THIS  AGREEMENT.  EACH  SHAREHOLDER
            IRREVOCABLY  WAIVES,  TO THE FULLEST  EXTENT  PERMITTED  BY LAW, ANY
            OBJECTION  WHICH IT MAY HAVE OR MAY HEREAFTER  HAVE TO THE LAYING OF
            THE VENUE OF ANY SUCH SUIT, ACTION OR PROCEEDING BROUGHT IN ANY SUCH
            COURT AND ANY CLAIM THAT ANY SUCH SUIT, ACTION OR PROCEEDING BROUGHT
            IN ANY SUCH COURT HAS BEEN BROUGHT IN AN  INCONVENIENT  FORUM.  EACH
            SHAREHOLDER AGREES THAT A FINAL AND  NON-APPEALABLE  JUDGMENT IN ANY
            SUCH SUIT,  ACTION OR PROCEEDING  BROUGHT IN ANY SUCH COURT SHALL BE
            CONCLUSIVE AND BINDING UPON SUCH  SHAREHOLDER AND MAY BE ENFORCED IN
            ANY OTHER COURTS TO THE  JURISDICTION  OF WHICH SUCH  SHAREHOLDER IS
            SUBJECT  BY A SUIT UPON SUCH  JUDGMENT,  PROVIDED  THAT  SERVICE  OF
            PROCESS IS  EFFECTED  UPON SUCH  SHAREHOLDER  IN ONE OF THE  MANNERS
            SPECIFIED IN PARAGRAPH 21 BELOW OR AS OTHERWISE PERMITTED BY LAW.

      xx.   Appointment of Agent. Each Shareholder hereby irrevocably designates
            and appoints  Prentice-Hall  Corporation  System,  Inc., 15 Columbus
            Circle,  New York, NY 10023,  as its authorized  agent to accept and
            acknowledge  on its behalf  service of any and all process which may
            be served in any suit,  action or proceeding of the nature  referred
            to in Paragraph 19 of this Agreement in any court

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            sitting in the City of New York,  State of New York,  in the City of
            Houston,  State of Texas, or in the City of Dallas,  State of Texas,
            respectively. Said designation and appointment shall be irrevocable.
            If such agent for service  shall cease so to act,  each  Shareholder
            covenants and agrees that it shall irrevocably designate and appoint
            without  delay  another such agent  satisfactory  to Agent and shall
            deliver  promptly to Agent evidence in writing of such other agent's
            acceptance of such appointment.

      xxi.  Service of  Process.  Each  Shareholder  hereby  consents to process
            being  served  in any  suit,  action  or  proceeding  of the  nature
            referred  to in  Paragraph  19 of this  Agreement  either (a) by the
            mailing of a copy thereof by registered mail (registered  airmail if
            addressed  to a  location  in a country  other  than the  country of
            mailing),  postage prepaid, return receipt requested, to the address
            for such Shareholder set forth below such  Shareholder's name on the
            signature  pages  hereof  or to any  other  address  of  which  such
            Shareholder  shall have given  written  notice to Agent  pursuant to
            Paragraph 14 of this Agreement or (b) by serving a copy thereof upon
            Prentice-Hall  Corporation  System,  Inc. at its appropriate address
            set forth in Paragraph 20 of this Agreement,  as such  Shareholder's
            agent for service of process  (provided  that,  to the extent lawful
            and possible, written notice of said service upon said agent of such
            Shareholder may be mailed by registered mail (registered  airmail if
            addressed  to a  location  in a country  other  than the  country of
            mailing),   postage  prepaid,  return  receipt  requested,  to  such
            Shareholder at its address  specified  above or to any other address
            of which such Shareholder shall have given written notice to Agent).
            Each Shareholder irrevocably waives, to the fullest extent permitted
            by law,  all claim of error by reason of any such service and agrees
            that such  service  (i) shall be deemed in every  respect  effective
            service of process upon such Shareholder in any such suit, action or
            proceeding and (ii) shall,  to the fullest extent  permitted by law,
            be taken and held to be valid  personal  service  upon and  personal
            delivery to such Shareholder.

      xxii. No Limitation on Service or Suit. Nothing in Paragraphs 19, 20 or 21
            of this Agreement shall (a) affect the right of Agent or any Bank to
            serve process in any manner  permitted by law or (b) limit the right
            of Agent or any Bank or other  holder to bring  proceedings  against
            any Shareholder in the courts of any other jurisdiction.

      xxiii.Financial  Reporting.  So long as this Agreement  remains in effect,
            Shareholders  agree that they will deliver to Agent,  in  sufficient
            copies  for  distribution  to all  Banks,  the  following  financial
            information:

                        (i)   As soon as the same become  available,  but in any
                              event within 120 (one  hundred  twenty) days after
                              the  end  of  the   fiscal   year,   the   audited
                              consolidated      financial     statements     and
                              consolidating    financial    statements    (which
                              consolidating

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                              financial  statements are not separately  reported
                              on  by  independent  public   accountants)  of  NL
                              Industries  and its  subsidiaries  for such fiscal
                              year and the  consolidating  financial  statements
                              (not separately  reported on by independent public
                              accountants)  of Kronos and its  subsidiaries  for
                              such fiscal year;  each  presented  in  conformity
                              with  U.S.   GAAP  with   changes  in   accounting
                              principles,  if any,  from the prior  fiscal year,
                              specified  in the  certificates  described  below,
                              together  with  certificates  executed  by a  Vice
                              President of NL Industries,  in form and substance
                              reasonably  satisfactory  to Agent,  and otherwise
                              certifying  that such  financial  statements  have
                              been  prepared in  accordance  with U.S.  GAAP and
                              fairly present the financial condition and results
                              of operation of the Persons subject thereof.

                        (ii)  Within  90  (ninety)  days  after  the end of each
                              fiscal  quarter  (excluding  the fourth  quarter),
                              unaudited consolidated and consolidating financial
                              statements of NL Industries  and its  subsidiaries
                              and unaudited  consolidating  financial statements
                              of Kronos and its subsidiaries;  each presented in
                              conformity   with  U.S.   GAAP  with   changes  in
                              accounting  principles,  if any,  from  the  prior
                              fiscal  year,   specified   in  the   certificates
                              described   below,   for   each   fiscal   quarter
                              (excluding the fourth  quarter),  and certificates
                              executed by a Vice President of NL Industries,  in
                              form  and  substance  reasonably  satisfactory  to
                              Agent,   and   otherwise   certifying   that  such
                              financial   statements   have  been   prepared  in
                              accordance  with U.S. GAAP and fairly  present the
                              financial  condition  and results of  operation of
                              the Persons subject thereof.

                        (iii) Promptly deliver notice thereof to Agent, upon the
                              commencement of any action or other proceedings by
                              or against any  Shareholder  under any bankruptcy,
                              insolvency or other similar law.

                        (iv)  Upon  request  of Agent,  furnish  Agent with such
                              information   about  the   business,   assets  and
                              financial  condition of any Shareholder and/or any
                              other Persons Controlled directly or indirectly by
                              such   Shareholder   as  Agent  or  any  Bank  may
                              reasonably  request,   provided,   however,   that
                              delivery of such information is subject to receipt
                              of an executed Confidentiality Agreement with

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                              respect  to   confidential   information  of  such
                              Shareholder or Person.



SECOND AMENDED AND RESTATED LIQUIDITY UNDERTAKING - Page 19



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      IN WITNESS WHEREOF, the undersigned have executed this Agreement effective
as of the date first written above.

                                    NL INDUSTRIES, INC.


                                    By:    /s/ Susan E. Alderton
                                    Name:  Susan E. Alderton
                                    Title: Vice President & Treasurer

                                    By:
                                    Name:
                                    Title:

                                    Address for Notices:

                                    70 East 55th Street
                                    New York, New York 10022
                                    Attention: Ms. Susan E. Alderton
                                    Telefax: 212-421-7209


                                    KRONOS, INC.


                                    By:    /s/ Susan E. Alderton
                                    Name:  Susan E. Alderton
                                    Title: Vice President & Treasurer


                                    By:
                                    Name:
                                    Title:

                                    Address for Notices:

                                    c/o NL Industries, Inc.
                                    70 East 55th Street
                                    New York, New York 10022
                                    Attention: Ms. Susan E. Alderton
                                    Telefax: 212-421-7209



SECOND AMENDED AND RESTATED LIQUIDITY UNDERTAKING - Page 20



<PAGE>


                           KRONOS INTERNATIONAL, INC.


                                    By:    /s/ E. Gaertner
                                    Name:  E. Gaertner
                                    Title: President


                                    By:    /s/ V. Roth
                                    Name:  V. Roth
                                    Title: Vice President & Controller


      The  undersigned  has executed  this  Agreement  solely for the purpose of
confirming receipt of this Agreement and reliance on this Agreement by Agent and
Banks effective as of the date first written above.

HYPOBANK INTERNATIONAL S.A.


By:     /s/ Michael Bisch
Name:   Michael Bisch
Title:  Charge de Service


By:
Name:
Title:

Address for Notices:

4, rue Alphonse Weicker
L-2721 Luxembourg-Kirchberg
Attention:  Michael Bisch
Telefax:    (011) 352-4272-4510


SECOND AMENDED AND RESTATED LIQUIDITY UNDERTAKING - Page 21



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