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                                                                   EXHIBIT 10.21

                               SEVERANCE AGREEMENT

      AGREEMENT by and between AMTROL INC., a Rhode Island corporation
("AMTROL"), AMTROL Holdings Inc., a Delaware corporation, ("Holdings" and
together with AMTROL, the "Company") and Christopher A. Laus (the "Executive"),
dated as of the 29th day of October, 2004.

      The Boards of Directors of Holdings and AMTROL (the "Boards") have
determined that it is in the best interests of the Company and its shareholders
to assure that the Company will have the continued service and dedication of the
Executive. In addition, the Boards believe it is imperative to diminish the
inevitable distraction of the Executive by virtue of the personal uncertainties
and risks created by a pending or threatened Change of Control and to encourage
the Executive's full attention and dedication to the Company currently and in
the event of any threatened or pending Change of Control, and to provide the
Executive with severance arrangements currently and upon a Change of Control
which ensure that the compensation expectations of the Executive will be
satisfied and which are competitive with those of other corporations. Therefore,
in order to accomplish these objectives, the Boards have caused the Company to
enter into this Agreement.

      NOW, THEREFORE, IT IS HEREBY AGREED AS FOLLOWS:

      1. In the event Executive's employment with the Company is terminated
without Cause (as defined below) within one (1) year subsequent to a Change of
Control (as defined below), AMTROL will continue Executive's then current annual
base salary for a period of twelve (12) months, subject to withholdings required
by law and other applicable deductions. In the event of a Change of Control,
Executive will only be entitled to receive the salary continuation payments
discussed above if the Executive's employment with the Company is involuntarily
terminated as a result of the Change of Control. Additionally, Executive will be
entitled to accelerated payment by AMTROL of any amounts earned pursuant to the
Management Incentive Compensation Plan as described in the summary to such plan
as of the date of termination of employment.

      For the purpose of this Agreement a "Change of Control" shall mean:

            (i) There shall have occurred a change in control which the Company
      would be required to report in response to Item 1 of Form 8-K promulgated
      under the Securities Exchange Act of 1934, as amended (the "Exchange
      Act"), or if such regulation is no longer in effect, any regulations
      promulgated by the Securities and Exchange Commission pursuant to the
      Exchange Act which are intended to serve similar purposes;

            (ii) The acquisition, other than from the Company, by any
      individual, entity or group (within the meaning of Section 13(d)(3) or
      14(d)(2) of the Exchange Act) of beneficial ownership (within the meaning
      of Rule 13d-3 promulgated under the Exchange Act) of 50% or more of either
      the then outstanding shares of common stock of the Company (the
      "Outstanding Company

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      Common Stock") or the combined voting power of the then outstanding voting
      securities of the Company entitled to vote generally in the election of
      directors (the "Company Voting Securities"), provided, however, that any
      acquisition by the Company or its subsidiaries, or any employee benefit
      plan (or related trust) of the Company or its subsidiaries, or any
      corporation with respect to which, following such acquisition, more than
      50% of, respectively, the then outstanding shares of common stock of such
      corporation and the combined voting power of the then outstanding voting
      securities of such corporation entitled to vote generally in the election
      of directors is then beneficially owned, directly or indirectly, by all or
      substantially all of the individuals and entities who were the beneficial
      owners, respectively, of the Outstanding Company Common Stock and Company
      Voting Securities immediately prior to such acquisition in substantially
      the same proportion as their ownership, immediately prior to such
      acquisition, of the Outstanding Company Common Stock and Company Voting
      Securities, as the case may be, shall not constitute a Change of Control;
      or

            (iii) Individuals who, as of January 1, 2004, constitute the Boards
      (the "Incumbent Boards") cease for any reason to constitute at least a
      majority of the Boards, provided that any individual becoming a director
      subsequent to January 1, 2004 whose election, or nomination for election
      by the Company's shareholders, was approved by a vote of at least a
      majority of the directors then comprising the Incumbent Boards shall be
      considered as though such individual were a member of the Incumbent
      Boards; or

            (iv) Approval by the stockholders of the Company of (x) a complete
      liquidation or dissolution of the Company, (y) the sale or other
      disposition of all or a material portion of the assets of the Company, or
      (z) a reorganization, merger or consolidation, in each case, with respect
      to which all or substantially all of the individuals and entities who were
      the respective beneficial owners of the Outstanding Company Common Stock
      and Company Voting Securities immediately prior to such reorganization,
      merger or consolidation do not, following such reorganization, merger or
      consolidation, beneficially own, directly or indirectly, more than 50% of,
      respectively, the then outstanding shares of common stock and the combined
      voting power of the then outstanding voting securities entitled to vote
      generally in the election of directors, as the case may be, of the
      corporation resulting from such reorganization, merger or consolidation;
      provided, however, "reorganization" for the purposes of this subsection
      1(iv)(z) shall not include any voluntary or involuntary bankruptcy or
      insolvency filing by or against the Company.

      For purposes of this Agreement, "Cause" means:

            (i) an act or acts of personal dishonesty taken by the Executive and
      intended to result in substantial personal enrichment of the Executive at
      the expense of the Company,

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            (ii) repeated violations by the Executive of the Executive's
      obligations of employment which are demonstrably willful and deliberate on
      the Executive's part and which are not remedied in a reasonable period of
      time after receipt of written notice from the Company, or

            (iii) the conviction of the Executive of a felony or a crime
      involving moral turpitude.

      2. Nothing in this Severance Agreement alters the "at-will" nature of
Executive's Employment with the Company.

      3. The salary continuation payments discussed above are in lieu of any
other severance or salary continuation payments to which Executive may have been
entitled pursuant to any agreements with the Company and/or Company policy or
practice.

      4. Executive is not entitled to any salary continuation payments pursuant
to this Severance Agreement in the event Executive resigns his employment with
the Company at any time prior to or subsequent to a Change of Control.

      5. In the event the Executive's employment is terminated at any time for
any reason, the Company agrees to provide Director's and Officer's liability
insurance for Executive for an appropriate tail period and to indemnify
Executive for any claims made against Executive as a result of his employment
with the Company.

      IN WITNESS WHEREOF, the Executive has hereunto set his hand and, pursuant
to the authorization from their Boards of Directors, AMTROL and Holdings have
caused these presents to be executed in their names on their behalf, all as of
the day and year first above written.

AMTROL Inc.                                   AMTROL Holdings Inc.

By: /s/ Albert D. Indelicato                  By: /s/ Albert D. Indelicato
    ------------------------                      ------------------------
        Albert D. Indelicato                          Albert D. Indelicato

EXECUTIVE

/s/ Christopher A. Laus
-----------------------
    Christopher A. Laus