<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
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<MULTIPLIER> 1,000
       
<S>                             <C>                     <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   6-MOS                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997             DEC-31-1997             DEC-31-1997
<PERIOD-START>                             JAN-01-1997             JAN-01-1997             JAN-01-1997
<PERIOD-END>                               MAR-31-1997             JUN-30-1997             SEP-30-1997
<CASH>                                            7644                   11480                   12460
<SECURITIES>                                         0                       0                       0
<RECEIVABLES>                                    21851                   25778                   29637
<ALLOWANCES>                                     (250)                   (250)                   (250)
<INVENTORY>                                      25346                   24835                   25839
<CURRENT-ASSETS>                                 60186                   67130                   73697
<PP&E>                                           40835                   41157                   41332
<DEPRECIATION>                                 (25715)                 (26771)                 (27841)
<TOTAL-ASSETS>                                   89769                   95888                  101420
<CURRENT-LIABILITIES>                            19806                   25175                   30415
<BONDS>                                              0                       0                       0
<PREFERRED-MANDATORY>                                0                       0                       0
<PREFERRED>                                          0                       0                       0
<COMMON>                                         97965                   98630                   98697
<OTHER-SE>                                     (29596)                 (29274)                 (28842)
<TOTAL-LIABILITY-AND-EQUITY>                     89769                   95888                  101420
<SALES>                                          19681                   39032                   63407
<TOTAL-REVENUES>                                 19681                   39032                   63407
<CGS>                                            12313                   23853                   39877
<TOTAL-COSTS>                                    19371                   38158                   61606
<OTHER-EXPENSES>                                  (15)                    (97)                   (191)
<LOSS-PROVISION>                                     0                       0                       0
<INTEREST-EXPENSE>                                   0                       0                       0
<INCOME-PRETAX>                                    295                     777                    1610
<INCOME-TAX>                                       114                     300                     621
<INCOME-CONTINUING>                                  0                       0                       0
<DISCONTINUED>                                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                       181                     477                     989
<EPS-PRIMARY>                                     0.01                    0.03                    0.06
<EPS-DILUTED>                                     0.01                    0.03                    0.06
        

</TABLE>