EMERSON ELECTRIC CO — Director's Dealing 2006

Jun 19, 2006

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MKS INSTRUMENTS INC (MKSI)
CIK: 0001049502
Period of Report: 2006-06-15

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
2006-06-15	Common Stock	S	39084	$19.7751	Disposed	5737388	Indirect
2006-06-16	Common Stock	S	72983	$19.3072	Disposed	5664405	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 15, 2006, as follows: 200 shares at $19.66; 200
at $19.68; 200 at $19.69; 3,000 at $19.70; 4,800 at $19.71; 1,100 at $19.72; 1,500 at $19.73; 1,790 at $19.74; 1,424 at
$19.75; 2,499 at $19.76; 2,100 at $19.77; 1,300 at $19.78; 1,590 at $19.79; 9,600 at $19.80; 1,400 at $19.81; 781 at $19.82;
300 at $19.83; 1,300 at $19.84; 600 at $19.85; 700 at $19.86; 600 at $19.87; 400 at $19.88; 400 at $19.89; 900 at $19.90;
and 400 at $19.92. The weighted average sales price for these transactions was $19.7751 per share.

F2: The reported securities are owned directly by Astec America Inc. The Reporting Person is the ultimate parent company of
Astec America Inc.

F3: The sales were effected in multiple transactions, at varying prices, on June 16, 2006, as follows and as described in
Footnotes 4 and 5 below: 2,500 shares at $19.00; 1,000 at $19.01; 1,200 at $19.02; 1,200 at $19.03; 500 at $19.04; 600 at
$19.05; 600 at $19.06; 526 at $19.07; 1,674 at $19.08; 1,200 at $19.09; 2,424 at $19.10; 1,769 at $19.11; 1,300 at $19.12;
625 at $19.13; 375 at $19.14; 2,300 at $19.15; 31 at $19.16; 500 at $19.17; 861 at $19.18; 867 at $19.19; 1,770 at $19.20;
500 at $19.21; 2 at $19.22; 419 at $19.23; 700 at $19.24; and 2,499 at $19.25.

F4: This footnote sets forth additional detail with respect to the transactions described in Footnote 3, as follows: 1,000 shares
at $19.26; 1,150 at $19.27; 1,901 at $19.28; 2,450 at $19.29; 5,107 at $19.30; 2,592 at $19.31; 2,681 at $19.32; 2,006 at
$19.33; 1,010 at $19.34; 665 at $19.35; 803 at $19.36; 427 at $19.37; 773 at $19.38; 1,098 at $19.39; 1,922 at $19.40; 2,286
at $19.41; 900 at $19.42; 800 at $19.43; 100 at $19.44; 1,100 at $19.45; 300 at $19.46; 909 at $19.47; 300 at $19.48; 1,200
at $19.49; and 800 at $19.50.

F5: This footnote sets forth additional detail with respect to the transactions described in Footnote 3, as follows: 1,249 shares
at $19.51; 500 at $19.52; 100 at $19.53; 400 at $19.54; 500 at $19.55; 100 at $19.56; 100 at $19.61; 200 at $19.62; 1,462 at
$19.64; 100 at $19.65; 84 at $19.66; 503 at $19.67; 216 at $19.68; 335 at $19.69; 1,106 at $19.70; 100 at $19.71; 700 at
$19.72; 200 at $19.73; 100 at $19.74; 1,506 at $19.75; 200 at $19.76; 800 at $19.77; and 200 at $19.78. The weighted
average sales price for these transactions was $19.3072 per share.

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