EMERSON ELECTRIC CO — Director's Dealing 2006

Jun 28, 2006

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MKS INSTRUMENTS INC (MKSI)
CIK: 0001049502
Period of Report: 2006-06-26

Reporting Person: EMERSON ELECTRIC CO (10% Owner)
Reporting Person: ASTEC AMERICA INC (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2006-06-26	Common Stock	S	25000	$19.6537	Disposed	5522405	Indirect
2006-06-27	Common Stock	S	25000	$19.6829	Disposed	5497405	Indirect

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	1065182	Direct

Footnotes

F1: The sales were effected in multiple transactions, at varying prices, on June 26, 2006, as follows and as described in
Footnote 2 below: 483 shares at $19.37; 700 at $19.38; 400 at $19.40; 617 at $19.41; 200 at $19.42; 400 at $19.43; 400 at
$19.44; 600 at $19.45; 300 at $19.46; 100 at $19.47; 300 at $19.48; 524 at $19.50; 200 at $19.51; 400 at $19.52; 200 at
$19.53; 300 at $19.54; 600 at $19.55; 400 at $19.56; 583 at $19.57; 900 at $19.60; 400 at $19.62; 400 at $19.63; 600 at
$19.66; 900 at $19.67; 1,000 at $19.68; and 1,280 at $19.69.

F2: This footnote sets forth additional detail with respect to the transactions described in Footnote 1, as follows: 744 shares
at $19.70; 669 at $19.71; 200 at $19.72; 330 at $19.73; 200 at $19.74; 2,700 at $19.75; 1,800 at $19.76; 1,300 at $19.77;
200 at $19.78; 400 at $19.79; 200 at $19.80; 800 at $19.81; 300 at $19.82; 700 at $19.83; 200 at $19.84; 200 at $19.85; 100
at $19.86; 570 at $19.87; and 200 at $19.88. The weighted average sales price for these transactions was $19.6537 per
share.

F3: The reported securities are owned directly by Astec America Inc. The Reporting Person is the ultimate parent company of
Astec America Inc.

F4: The sales were effected in multiple transactions, at varying prices, on June 27, 2006, as follows and as described in
Footnote 5 below: 100 shares at $19.48; 700 at $19.49; 500 at $19.50; 100 at $19.51; 500 at $19.52; 500 at $19.53; 100 at
$19.54; 359 at $19.55; 200 at $19.56; 300 at $19.57; 800 at $19.58; 1,300 at $19.59; 2,844 at $19.60; 1,680 at $19.61; 377
at $19.62; 323 at $19.63; 633 at $19.64; 500 at $19.65; 300 at $19.66; 1,200 at $19.67; 500 at $19.68; 1,200 at $19.69; 100
at $19.70; 1,200 at $19.71; and 500 at $19.72.

F5: This footnote sets forth additional detail with respect to the transactions described in Footnote 4, as follows: 400 shares
at $19.73; 421 at $19.74; 560 at $19.75; 384 at $19.76; 500 at $19.78; 200 at $19.79; 1,219 at $19.80; 100 at $19.81; 300 at
$19.82; 800 at $19.83; 324 at $19.84; 576 at $19.85; 200 at $19.86; 189 at $19.87; 1,211 at $19.88; 300 at $19.89; 200 at
$19.90; 100 at $19.91; and 200 at $20.04. The weighted average sales price for these transactions was $19.6829 per share.

F6: The reported securities are owned directly by Emerson Electric Co.