EMERSON ELECTRIC CO — Director's Dealing 2006

Jun 30, 2006

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MKS INSTRUMENTS INC (MKSI)
CIK: 0001049502
Period of Report: 2006-06-28

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
2006-06-28	Common Stock	S	25000	$19.3720	Disposed	5472405	Indirect
2006-06-29	Common Stock	S	25000	$20.0346	Disposed	5447405	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 28, 2006, as follows and as described in
Footnote 2 below: 300 shares at $19.14; 300 at $19.15; 200 at $19.16; 200 at $19.17; 500 at $19.18; 100 at $19.19; 500 at
$19.20; 300 at $19.22; 200 at $19.23; 600 at $19.24; 300 at $19.25; 500 at $19.26; 1,300 at $19.27; 500 at $19.28; 300 at
$19.29; 500 at $19.30; 200 at $19.31; 1,000 at $19.32; 1,425 at $19.33; 1,000 at $19.34; 200 at $19.35; 1,400 at $19.36;
1,100 at $19.37; 800 at $19.38; 500 at $19.39; and 300 at $19.40.

F2: This footnote sets forth additional detail with respect to the transactions described in Footnote 1, as follows: 1,100 shares
at $19.41; 1,159 at $19.42; 1,100 at $19.43; 1,400 at $19.44; 400 at $19.45; 350 at $19.46; 700 at $19.47; 400 at $19.48;
100 at $19.49; 300 at $19.50; 200 at $19.51; 1,700 at $19.52; 400 at $19.53; 100 at $19.54; 66 at $19.55; 500 at $19.56; 100
at $19.57; 200 at $19.59; and 200 at $19.63. The weighted average sales price for these transactions was $19.372 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 29, 2006, as follows and as described in
Footnote 5 below: 200 shares at $19.69; 200 at $19.71; 200 at $19.72; 400 at $19.73; 500 at $19.74; 208 at $19.75; 200 at
$19.76; 200 at $19.78; 700 at $19.79; 100 at $19.80; 200 at $19.81; 1,000 at $19.82; 200 at $19.83; 496 at $19.84; 600 at
$19.85; 665 at $19.86; 1,139 at $19.87; 700 at $19.88; 800 at $19.89; 900 at $19.90; 300 at $19.91; 1,400 at $19.92; 600 at
$19.93; 1,900 at $19.94; 1,200 at $19.95; 500 at $19.96; 200 at $19.97; 500 at $19.98; and 1,019 at $19.99.

F5: This footnote sets forth additional detail with respect to the transactions described in Footnote 4, as follows: 200 shares
at $20.01; 100 at $20.03; 100 at $20.08; 100 at $20.11; 300 at $20.12; 100 at $20.13; 48 at $20.16; 200 at $20.22; 181 at
$20.29; 19 at $20.30; 900 at $20.31; 200 at $20.32; 100 at $20.33; 200 at $20.34; 500 at $20.35; 100 at $20.37; 200 at
$20.38; 400 at $20.39; 100 at $20.40; 207 at $20.41; 293 at $20.42; 200 at $20.44; 200 at $20.46; 200 at $20.48; 500 at
$20.49; 1,100 at $20.50; 625 at $20.51; and 400 at $20.52. The weighted average sales price for these transactions was
$20.0346 per share.

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