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                                                                   EXHIBIT 10.18

                          [UNITED DOMINION Letterhead]




                                 April 28, 1999



Mr. William R. Holland
Chairman and Chief Executive Officer
United Dominion Industries Limited
2300 One First Union Center
301 S. College Street
Charlotte, NC 28202

Re:      Supplemental Executive Retirement Plan

Dear Bill:

The purpose of this letter is to recite the agreement between you and the
Company, as approved by the Company's Compensation and Human Resources Committee
("CHRC"), regarding your benefit under the Company's Supplemental Executive
Retirement Plan ("SERP").

Under the current SERP plan design, upon your retirement at age 62, you are
eligible to receive your accrued SERP benefit in the form of a life annuity,
with a right of survivorship in your spouse. If you elect to retire before you
reach 62, your benefit is reduced using an actuarial factor to reflect the early
commencement of benefits. Additionally, in the event there is a "Change in
Control" (as defined in the SERP), you will receive your SERP benefit in a
single lump sum payment, calculated using the GATT discount rate determined from
time to time under the United Dominion Retirement Plan for Salaried Employees
(the "GATT rate").

The modifications to your SERP benefit are as follows:

Your SERP benefit will be paid in a single lump sum payment if your employment
terminates under any of the following circumstances prior to a Change in
Control:

         1.       retirement upon reaching age 62, or thereafter
         2.       death or "Disability" (as defined under the SERP), or
         3.       termination without "Good Cause" (as defined in the Company's
                  Corporate Office Severance Policy, as amended from time to
                  time).

In any of these events, the amount of the lump sum would be computed (i) using
the GATT rate in effect as of the date of such termination, and (ii) in the case
of your death, Disability



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or termination without Good Cause occurring before age 62, without regard to the
early retirement reduction factors that would otherwise apply to a SERP benefit
commencing before age 62. The lump sum would be paid to you on or about the
first business day of January of the calendar year following the calendar year
in which your employment terminates.

If you wish to waive this lump sum payment and receive the annuity benefits
otherwise provided for under the SERP, you must provide the Company with written
notice of this election before December 1, 1999, which election must be
irrevocable. If you chose to waive the lump sum payment and your employment
terminates prior to a Change in Control as a result of your death, Disability or
termination without Good Cause occurring before you reach age 62, your annuity
payments from the SERP will be calculated without regard to the early retirement
reduction factors that would otherwise apply to a SERP benefit commencing before
age 62.

Nothing in this letter is intended to modify your benefits provided under the
March 1, 1999 Change in Control agreement between you and the Company, or the
current provisions of the SERP regarding the lump sum payment of the "Commuted
Payment Amount" of your SERP benefits if your employment terminates after a
Change in Control.

Please sign below to acknowledge and agree to the changes described above. If
you have any questions on this subject, please don't hesitate to call Tim
Verhagen or me at any time.

Best regards,
UNITED DOMINION INDUSTRIES LIMITED


/s/ Dalton D. Ruffin

Dalton D. Ruffin
Chairman, Compensation and
Human Resources Committee

Accepted:


/s/ William R. Holland
-----------------------------------
William R. Holland





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