<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<RESTATED>
<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-END>                               MAR-31-1997             JUN-30-1997             SEP-30-1997
<CASH>                                           5,695                   3,357                   1,252
<SECURITIES>                                         0                       0                       0
<RECEIVABLES>                                   23,404                  30,809                  35,035
<ALLOWANCES>                                         0                       0                       0
<INVENTORY>                                     13,890                  16,936                  20,388
<CURRENT-ASSETS>                                48,561                  57,114                  62,676
<PP&E>                                          17,919                  19,861                  21,858
<DEPRECIATION>                                   5,620                   6,427                   7,339
<TOTAL-ASSETS>                                  62,388                  71,474                  78,420
<CURRENT-LIABILITIES>                           14,417                  18,320                  19,423
<BONDS>                                              0                       0                       0
<PREFERRED-MANDATORY>                                0                       0                       0
<PREFERRED>                                          0                       0                       0
<COMMON>                                        13,854                  14,679                  15,879
<OTHER-SE>                                           0                       0                       0
<TOTAL-LIABILITY-AND-EQUITY>                    62,388                  71,474                  78,420
<SALES>                                         31,341                  68,839                 107,221
<TOTAL-REVENUES>                                31,511                  69,236                 107,745
<CGS>                                           16,105                  36,165                  56,574
<TOTAL-COSTS>                                   16,105                  36,165                  56,574
<OTHER-EXPENSES>                                 9,764                  21,031                  32,320
<LOSS-PROVISION>                                     0                       0                       0
<INTEREST-EXPENSE>                                   0                       0                       0
<INCOME-PRETAX>                                  5,706                  12,182                  18,954
<INCOME-TAX>                                     2,012                   4,265                   6,594
<INCOME-CONTINUING>                              3,694                   7,917                  12,360
<DISCONTINUED>                                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                     3,694                   7,917                  12,360
<EPS-PRIMARY>                                      .33                     .70                    1.09
<EPS-DILUTED>                                      .31                     .66                    1.03


</TABLE>