Document:

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                                                          Executed in 6 Parts
                                                          Counterpart No. (   )

                              NATIONAL EQUITY TRUST

                          LOW FIVE PORTFOLIO SERIES 31

                            REFERENCE TRUST AGREEMENT

                  This Reference Trust Agreement dated , 2000 among Prudential
Securities Incorporated, as Depositor and The Chase Manhattan Bank, as Trustee,
sets forth certain provisions in full and incorporates other provisions by
reference to the document entitled "National Equity Trust Low Five Portfolio
Series, Trust Indenture and Agreement" (the "Basic Agreement") dated April 25,
1995. Such provisions as are set forth in full herein and such provisions as are
incorporated by reference constitute a single instrument (the "Indenture").

                                WITNESSETH THAT:

                  In consideration of the premises and of the mutual agreements
herein contained, the Depositor and the Trustee agree as follows:

                                     Part I.

                     STANDARD TERMS AND CONDITIONS OF TRUST

                  Subject to the provisions of Part II hereof, all the
provisions contained in the Basic Agreement are herein incorporated by reference
in their entirety and shall be deemed to be a part of this instrument as fully
and to the same extent as though said provisions had been set forth in full in
this instrument except that the Basic Agreement is hereby amended in the
following manner:

A.       Article I, entitled "Definitions", paragraph 22, shall be amended as
         follows:

                  "Trustee shall mean the Chase Manhattan Bank, or any
                  successor trustee appointed as hereinafter provided."

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B.       Article II, entitled "Deposit of Securities; Acceptance of Trust",
         shall be amended as follows:

         The second sentence of Section 2.03 Issue of Units shall be amended by
         deleting the words "on any day on which the Depositor is the only Unit
         Holder".

C.       Article III, entitled "Administration of Trust", shall be amended as
         follows:

         (i)      Section 3.01 Initial Costs shall be amended to substitute the
                  following language:

                  Section 3.01. Initial Cost The costs of organizing the Trust
                  and sale of the Trust Units shall, to the extent of the
                  expenses reimbursable to the Depositor provided below, be
                  borne by the Unit Holders, provided, however, that, to the
                  extent all of such costs are not borne by Unit Holders, the
                  amount of such costs not borne by Unit Holders shall be borne
                  by the Depositor and, provided further, however, that the
                  liability on the part of the Depositor under this section
                  shall not include any fees or other expenses incurred in
                  connection with the administration of the Trust subsequent to
                  the deposit referred to in Section 2.01. Upon notification
                  from the Depositor that the primary offering period is
                  concluded, the Trustee shall withdraw from the Account or
                  Accounts specified in the Prospectus or, if no Account is
                  therein specified, from the Principal Account, and pay to the
                  Depositor the Depositor's reimbursable expenses of organizing
                  the Trust and sale of the Trust Units in an amount certified
                  to the Trustee by the Depositor. If the balance of the
                  Principal Account is insufficient to make such withdrawal, the
                  Trustee shall, as directed by the Depositor, sell Securities
                  identified by the Depositor, or distribute to the Depositor
                  Securities having a value, as determined under Section 4.01 as
                  of the date of distribution, sufficient for such
                  reimbursement. The reimbursement provided for in this section
                  shall be for the account of the Unitholders of record at the
                  conclusion of the primary offering period and shall not be
                  reflected in the computation of the Unit Value prior thereto.
                  As used herein, the Depositor's reimbursable

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                  expenses of organizing the Trust and sale of the Trust Units
                  shall include the cost of the initial preparation and
                  typesetting of the registration statement, prospectuses
                  (including preliminary prospectuses), the indenture, and other
                  documents relating to the Trust, SEC and state blue sky
                  registration fees, the cost of the initial valuation of the
                  portfolio and audit of the Trust, the initial fees and
                  expenses of the Trustee, and legal and other out-of-pocket
                  expenses related thereto, but not including the expenses
                  incurred in the printing of preliminary prospectuses and
                  prospectuses, expenses incurred in the preparation and
                  printing of brochures and other advertising materials and any
                  other selling expenses. Any cash which the Depositor has
                  identified as to be used for reimbursement of expenses
                  pursuant to this Section shall be reserved by the Trustee for
                  such purpose and shall not be subject to distribution or,
                  unless the Depositor otherwise directs, used for payment of
                  redemptions in excess of the per-Unit amount allocable to
                  Units tendered for redemption. As directed by the Depositor,
                  the Trustee will advance funds to the Trust in an amount
                  necessary to reimburse the Depositor pursuant to this Section
                  and shall recover such advance from the sale or sales of
                  Securities at such time as the Depositor shall direct, but in
                  no event later than the termination of the Trust. Repayment of
                  any such advance shall be secured by a lien on the assets of
                  the Trust prior to the interest of the Unit Holders as
                  provided in Section 6.04.

         (ii)     The third paragraph of Section 3.05 Distribution shall be
                  amended to add the following sentence at the end thereof:

                  "The Trustee shall make a special distribution of the cash
                  balance in the Income and Principal accounts available for
                  such distribution to Unit Holders of record on such dates as
                  the Depositor shall direct, provided however, that no such
                  distribution shall be made if the assets of the Trust
                  subsequent to such distribution would not exceed any Deferred
                  Sales Charge payable and other trust expenses."

         (iii)    The second to the last paragraph of Section 3.08 Sale of
                  Securities shall be amended to replace the word "equal" with
                  the following phrase: "be sufficient to pay."

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D.       Reference to United States Trust Company of New York in its capacity as
         Trustee is replaced by the Chase Manhattan Bank throughout the Basic
         Agreement.

                                    Part II.

                      SPECIAL TERMS AND CONDITIONS OF TRUST

         The following special terms and conditions are hereby agreed to:

         A. The Trust is denominated National Equity Trust, Low Five Portfolio
Series 31.

         B. The Units of the Trust shall be subject to a deferred sales charge.

         C. The contracts for the purchase of common stock listed in Schedule A
hereto are those which, subject to the terms of this Indenture, have been or are
to be deposited in Trust under this Indenture as of the date hereof.

         D. The term "Depositor" shall mean Prudential Securities Incorporated.

         E. The aggregate number of Units referred to in Sections 2.03 and 9.01
of the Basic Agreement is as of the date hereof.

         F. A Unit of the Trust is hereby declared initially equal to 1/ th of
the Trust.

         G. The term "First Settlement Date" shall mean , 2000.

         H. The terms "Computation Day" and "Record Date" shall mean 10, 10, 10,
and 10.

         I. The term "Distribution Date" shall mean 25, 25, 25, and 25.

         J. The term "Termination Date" shall mean , 2001.

         K. The Trustee's Annual Fee shall be $ (per 1,000 Units) for
100,000,000 and above units outstanding; $0.80 (per 1,000 Units) for 50,000,000
- 99,999,999 units outstanding; $0.86 (per 1,000 Units) for 49,999,999 and below
units outstanding. In calculating the Trustee's annual fee, the fee applicable
to the number of units outstanding shall apply to all units outstanding.

         L. The Depositor's Portfolio supervisory service fee shall be $0.25 per
1,000 Units.

               [Signatures and acknowledgments on separate pages]EXHIBIT 4.3

                            CERTIFICATE OF AMENDMENT
                                 BY DIRECTORS OF
                                BELMONT BANCORP.

     Wilbur R. Roat, who is the President of the above-named Ohio corporation
for profit, does hereby certify that:

     A meeting of the directors was duly called and held on November 15, 1999.

The following resolution was adopted pursuant to Section 1701.70(B)(1) of the
Ohio Revised Code:

     RESOLVED, that the Articles of Incorporation of the Corporation be, and
     they hereby are, amended to fix the designations, rights, preferences,
     qualifications, limitations and restrictions of the Corporation's Series A
     Convertible Preferred Stock as provided in the designations of Rights and
     Preferences attached hereto as Exhibit A.

     RESOLVED, FURTHER, that 20,000 shares of the Corporation's preferred stock
     be designated as Series A Convertible Preferred Stock.

     IN WITNESS WHEREOF, the above named officer, acting on behalf of the
Corporation, has hereunto subscribed his name on December 21, 1999.

                                                     BY: /S/ WILBUR R. ROAT
                                                         ----------------------
                                                     TITLE: PRESIDENT

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                    EXHIBIT A TO CERTIFICATE OF AMENDMENT OF
                                BELMONT BANCORP.

                                BELMONT BANCORP.
                     Designations of Rights and Preferences
                                       of
                            Series A Preferred Stock

     RESOLVED, that pursuant to the authority granted to and vested in the Board
of Directors of Belmont Bancorp (the "Corporation") in accordance with the
provisions of the Articles of Incorporation, as amended, the Board of Directors
hereby creates a series of Preferred Stock, par value $.0001 per share, of the
Corporation and hereby states the designation and authorized number of shares of
such Preferred Stock, and fixes the relative rights, preferences, and
limitations thereof, as follows:

                      Series A Convertible Preferred Stock

     Section 1. Designation and Amount. The shares of such series shall be
designated as "Series A Convertible Preferred Stock" (the "Series A Preferred
Stock") and the number of shares constituting the Series A Preferred Stock shall
be twenty thousand (20,000) shares. Such number of shares may be increased or
decreased by resolution of the Board of Directors; provided, that no decrease
shall reduce the number of shares of Series A Preferred Stock to a number less
than the number of shares then outstanding plus the number of shares reserved
for issuance upon the exercise of outstanding options, rights, or warrants or
upon the conversion of any outstanding securities issued by the Corporation
convertible into Series A Preferred Stock.

     Section 2. Dividends and Distributions. The holders of shares of Series A
Preferred Stock shall be entitled to receive out of funds legally available for
the purpose dividends in an amount per share equal to any per share dividend
paid on the Common Stock, payable from legally available funds simultaneously
with the payment of such Common Stock dividend, when and if any such dividend
shall be declared by the Board of Directors.

     Section 3. Voting Rights. The Series A Preferred Stock shall vote as a
single class with the Common Stock (and any other shares issued from time to
time with like rights to vote as a single class with the Common Stock) on all
actions to be taken by the stockholders of the Corporation. Each share of Series
A Preferred Stock shall entitle the holder thereof to one (1) vote per share on
each such action to be taken.

     Section 4. Certain Restrictions. The Corporation shall not:

     (i)  declare or pay dividends, or make any other distributions, on any
          shares of Common Stock unless dividends are paid ratably on the Series
          A Preferred Stock and the Common Stock; or

     (ii) redeem or purchase or otherwise acquire for consideration shares of
          any stock ranking junior (either as to dividends or upon liquidation,
          dissolution, or

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          winding up) to the Series A Preferred Stock, provided that the
          Corporation may at any time redeem, purchase, or otherwise acquire
          shares of any such junior stock in exchange for shares of any stock of
          the Corporation ranking junior (either as to dividends or upon
          dissolution, liquidation, or winding up) to the Series A Preferred
          Stock.

     Section 5. Reacquired Shares. Any shares of Series A Preferred Stock
purchased or otherwise acquired by the Corporation in any manner whatsoever
shall be retired and canceled promptly after the acquisition thereof. All such
shares shall upon their cancellation become authorized but unissued shares of
Preferred Stock, but may not be reissued.

     Section 6. Liquidation, Dissolution, or Winding Up. Upon any liquidation,
dissolution, or winding up of the Corporation, whether voluntary or involuntary,
no distribution shall be made to the holders of shares of stock ranking junior
(either as to dividends or upon liquidation, dissolution, or winding up) to the
Series A Preferred Stock unless, prior thereto, the holders of shares of Series
A Preferred Stock shall have received $.0001 per share (such amount payable with
respect to one share of Series A Preferred Stock being sometimes referred to as
the "Liquidation Preference"). If upon such liquidation, dissolution or winding
up of the Corporation, whether voluntary or involuntary, the assets to be
distributed among the holders of Series A Preferred Stock shall be insufficient
to permit payment to the holders of Series A Preferred Stock of the full
Liquidation Preference, then the entire assets of the Corporation to be so
distributed shall be distributed ratably among the holders of Series A Preferred
Stock. Upon any such liquidation, dissolution or winding up of the Corporation,
after the holders of Series A Preferred Stock shall have been paid in full the
Liquidation Preference, the remaining net assets of the Corporation may be
distributed, next, to the holders of any stock ranking on liquidation junior to
the Series A Preferred Stock but senior to the Common Stock and, thereafter,
ratably to the holders of the Common Stock and the Series A Preferred Stock.

     Section 7. Redemption The shares of Series A Preferred Stock may be
redeemed in whole or in part by the Corporation at any time at its option at a
redemption price of $100.00 per share, plus the amount of dividends declared but
unpaid at the date of redemption. The Corporation shall provide the holders of
Series A Preferred Stock at least five business days' advance notice of its
election to redeem the Series A Preferred Stock, which notice shall either (i)
state the effective date of redemption or (ii) advise that the redemption shall
be effected upon the completion of any financing or offering and state the
estimated effective date of redemption based upon the date on which the
financing or offering is expected to be completed. If less than all the shares
of Series A Preferred Stock are redeemed, the redemption shall be effected on a
pro rata basis.

     Section 8. Rank. Unless the holders of more than 50% of the issued and
outstanding shares of Series A Preferred Stock shall otherwise approve, the
Series A Preferred Stock shall rank, with respect to the payment of the
distribution of assets upon liquidation to the extent provided in Section 6
hereof, senior to all other series and classes of the Corporation's capital
stock, including without limitation all other series of the Corporation's
Preferred Stock.

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     Section 9. Conversion.

     (A) Option to Convert. Each share of Series A Preferred Stock may be
converted in whole or in part into Common Stock at the option of either the
holder or the Corporation at any time on or after the later of (i) the date the
Corporation commences a public offering of its Common Stock or (ii) March 1,
2000. Upon conversion, the holder shall receive such number of shares of Common
Stock determined by dividing $100.00 per share, plus the amount of dividends
declared but unpaid at the date of conversion by (i) the closing price of the
Common Stock on the Nasdaq Stock Market as reported in The Wall Street Journal
at the close of trading on last business day ended as of the effective time of
the conversion (or, if not then trading on the Nasdaq Stock Market, such market
price as the Board of Directors shall reasonably determine) unless the
Corporation is then conducting (or has completed immediately prior to the
effective time of the conversion) a public offering of its Common Stock or (ii)
the price at which the Corporation is then offering its Common Stock in a public
offering (or has offered in a public offering completed immediately prior to the
effective time of the conversion) (the "Effective Price").

     (B) Notice of Election. The election to convert Series A Preferred Stock
into Common Stock shall be made by written notice delivered by the holder to the
Corporation or by the Corporation to the holder, as the case may be, and shall
be effective at such time as the Corporation shall determine, which shall not be
later than ten (10) business days after the notice of conversion is received,
unless the Corporation is then conducting a public offering of its Common Stock
and the number of shares of Common Stock issuable to the holder upon conversion
will be determined by reference to the offering price of the Common Stock, in
which event, the conversion may be effective at any time during the public
offering or within one business day after completion of the public offering, all
as determined by the Corporation.

     (C) Conversion Mechanics. At or prior to the effective time of conversion
pursuant to this Section 9, the holder shall surrender the certificate or
certificates therefor to the Corporation, duly endorsed in blank for transfer,
accompanied, in the case of an election to convert made by the holder, a written
notice of such election on such form as may be prescribed from time to time by
the Corporation. Notwithstanding the foregoing, if the holder shall fail to
deliver certificates evidencing the Series A Preferred Stock upon conversion,
the Corporation may deem the conversion to have been effected, in which event
any certificates which evidenced the Series A Preferred Stock shall be deemed to
evidence such number of shares of Common Stock as the holder has become entitled
to receive. If any fractional share of Common Stock would be delivered upon such
conversion, the Corporation, in lieu of delivering such fractional share, shall
pay to the holder an amount in cash equal to Effective Price.

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