April 22, 2005 via U.S. mail and facsimile Michael A. McLain, President and Chief Executive Officer Aearo Company I 5457 West 79th Street Indianapolis, IN 46268 	Re: 	Form 10-K for the fiscal year ended September 30, 2004 		Form 10-Q for the period ended December 31, 2004 			File No. 333-116676 Dear Mr. McLain: 	We have completed our review of your Form 10-K and related filings and have no further comments at this time. 								Sincerely, 								Rufus Decker 								Accounting Branch Chief ?? ?? ?? ?? Mr. Gary T. Steele March 9, 2005 Page 1 of 1 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549-0510 DIVISION OF CORPORATION FINANCE