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EXHIBIT 23.4
CONSENT OF INDEPENDENT ACCOUNTANTS
We hereby consent to the incorporation by reference in this Amendment No. 1
to the Registration Statement on Form S-4 of MKS Instruments, Inc. of our report
dated January 28, 2000, relating to the financial statements, which appears in
MKS Instruments, Inc.'s 1999 Annual Report to Stockholders, which is
incorporated by reference in its Annual Report on Form 10-K for the year ended
December 31, 1999. We also consent to the incorporation by reference of our
report dated January 28, 2000 relating to the financial statement schedule,
which appears in such Annual Report on Form 10-K. We also consent to the
references to us under the headings "Experts" and "Selected Financial Data" in
such Registration Statement.
/s/ PricewaterhouseCoopers LLP
PricewaterhouseCoopers LLP
Boston, Massachusetts
December 13, 2000
