EMERSON ELECTRIC CO — Director's Dealing 2006

Jun 7, 2006

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MKS INSTRUMENTS INC (MKSI)
CIK: 0001049502
Period of Report: 2006-06-05

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
2006-06-05	Common Stock	S	20000	$21.033	Disposed	6187436	Indirect
2006-06-06	Common Stock	S	29771	$21.0663	Disposed	6157665	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 5, 2006, as follows: 500 shares at $20.88; 127
at $20.89; 600 at $20.91; 2,300 at $20.92; 1,200 at $20.93; 924 at $20.94; 1,221 at $20.95; 749 at $20.96; 300 at $20.97;
200 at $20.98; 200 at $20.99; 1,200 at $21.05; 500 at $21.06; 600 at $21.07; 900 at $21.08; 1,600 at $21.09; 2,600 at
$21.10; 1,500 at $21.11; 300 at $21.12; 500 at $21.14; 200 at $21.15; 200 at $21.16; 1,035 at $21.17; 483 at $21.18; and 61
at $21.22. The weighted average sales price for these transactions was $21.0330 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 6, 2006, as follows and as described in Footnote
4 below: 200 shares at $20.73; 200 at $20.75; 200 at $20.76; 200 at $20.77; 100 at $20.78; 200 at $20.79; 400 at $20.80;
400 at $20.82; 188 at $20.83; 400 at $20.84; 200 at $20.85; 200 at $20.86; 100 at $20.87; 200 at $20.88; 100 at $20.89; 200
at $20.90; 900 at $20.91; 700 at $20.92; 100 at $20.93; 300 at $20.94; 200 at $20.96; 500 at $20.97; 500 at $20.98; 900 at
$21.00; 1,100 at $21.01; 1,283 at $21.02; 487 at $21.03; 400 at $21.04; 170 at $21.05; 1,100 at $21.06; 1,830 at $21.07;
1,513 at $21.08; 1,300 at $21.09; and 1,300 at $21.10.

F4: This footnote sets forth additional detail with respect to the transactions described in Footnote 3, as follows: 500 shares
at $21.11; 400 at $21.12; 200 at $21.13; 600 at $21.14; 1,000 at $21.15; 700 at $21.16; 200 at $21.17; 900 at $21.18; 800 at
$21.19; 3,900 at $21.20; 1,000 at $21.21; 400 at $21.22; 400 at $21.23; 300 at $21.24; 200 at $21.25; and 200 at $21.26. The
weighted average sales price for these transactions was $21.0663 per share.

F5: The reported securities are owned directly by Emerson Electric Co.