<TABLE> <S> <C>

<PAGE>
 
<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
CONDENSED STATEMENT OF OPERATIONS, THE CONDENSED BALANCE SHEET AND THE
ACCOMPANYING NOTES TO THE CONDENSED FINANCIAL STATEMENTS, AND IS QUALIFIED IN
ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
       
<S>                                     <C>                     <C>
<PERIOD-TYPE>                           3-MOS                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-1998<F1>         DEC-31-1997
<PERIOD-START>                             JUL-01-1998             JUL-01-1997
<PERIOD-END>                               SEP-30-1998             SEP-30-1997
<CASH>                                           2,284                   1,184
<SECURITIES>                                         0                       0
<RECEIVABLES>                                  103,507                  78,461
<ALLOWANCES>                                         0                       0
<INVENTORY>                                     58,705                  42,253
<CURRENT-ASSETS>                               175,361                 128,265
<PP&E>                                          23,443                  17,862
<DEPRECIATION>                                       0                       0
<TOTAL-ASSETS>                                 238,079                 177,723
<CURRENT-LIABILITIES>                          101,826                  67,355
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                            31                      29
<OTHER-SE>                                     123,440                  98,717
<TOTAL-LIABILITY-AND-EQUITY>                   238,079                 177,723
<SALES>                                         93,645                  87,007
<TOTAL-REVENUES>                                93,645                  87,007
<CGS>                                           52,403                  47,318
<TOTAL-COSTS>                                   52,403                  47,318
<OTHER-EXPENSES>                                24,456                  20,802
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                               1,648                     910
<INCOME-PRETAX>                                 11,755                  17,852
<INCOME-TAX>                                     4,526                   7,085
<INCOME-CONTINUING>                              7,229                  10,767
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                     7,229                  10,767
<EPS-PRIMARY>                                    $0.58                   $0.96
<EPS-DILUTED>                                    $0.57                   $0.92
<FN>
<F1>SEE NOTE 7 TO THE CONDENSED CONSOLIDATED FINANCIAL STATEMENTS.
</FN>
        


</TABLE>