CERTIFICATION

I, Michael A. McLain, Principal Executive Officer of Aearo Corporation,  certify
that:

     I have reviewed this quarterly report on Form 10-Q of Aearo Corporation;

     Based on my knowledge,  this  quarterly  report does not contain any untrue
statement of a material fact or omit to state a material fact  necessary to make
the statements made, in light of the  circumstances  under which such statements
were made, not  misleading  with respect to the period covered by this quarterly
report;

     Based on my  knowledge,  the  financial  statements,  and  other  financial
information  included in this quarterly  report,  fairly present in all material
respects the financial  condition,  results of operations  and cash flows of the
registrant as of, and for, the periods presented in this quarterly report;

     The  registrant's  other  certifying  officer  and  I are  responsible  for
establishing and maintaining  disclosure  controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal  control over financial
reporting  (as defined in Exchange Act Rules  13a-15(f) and  15d-15(f))  for the
registrant and have:

          a) Designed such disclosure  controls and  procedures,  or caused such
     disclosure controls and procedures to be designed under our supervision, to
     ensure that material information relating to the registrant,  including its
     consolidated  subsidiaries,  is made  known to us by  others  within  those
     entities,  particularly during the period in which this quarterly report is
     being prepared;

          b) Designed such internal control over financial reporting,  or caused
     such internal  control over  financial  reporting to be designed  under our
     supervision,  to provide reasonable  assurance regarding the reliability of
     financial  reporting  and  the  preparation  of  financial  statements  for
     external  purposes  in  accordance  with  generally   accepted   accounting
     principles;

          c) Evaluated the effectiveness of the registrant's disclosure controls
     and procedures and presented in this quarterly report our conclusions about
     the effectiveness of the disclosure controls and procedures,  as of the end
     of the period covered by this report based on such evaluation; and

          d) Disclosed in this quarterly  report any change in the  registrant's
     internal  control  over  financial   reporting  that  occurred  during  the
     registrant's  most recent fiscal quarter that has materially  affected , or
     is  reasonably  likely to  materially  affect,  the  registrant's  internal
     control over financial reporting; and

     The registrant's  other certifying  officer and I have disclosed,  based on
our most recent evaluation of internal control over financial reporting,  to the
registrant's auditors and the audit committee of registrant's board of directors
(or person performing the equivalent functions):

          a) All significant  deficiencies and material weaknesses in the design
     or  operation  of  internal  control  over  financial  reporting  which are
     reasonably  likely to adversely affect the registrant's  ability to record,
     process, summarize and report financial information; and

          b) Any fraud,  whether or not material,  that  involves  management or
     other employees who have a significant  role in the  registrant's  internal
     control over financial reporting.

Date:  August 14, 2003

                              /s/ Michael A. McLain
                              -------------------------
                              Michael A. McLain
                              Chief Executive Officer, President and
                              Chairman of the Board
                              (Principal Executive Officer)