<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-START>                             JAN-01-1997             JAN-01-1997             JAN-01-1997
<PERIOD-END>                               MAR-31-1997             JUN-30-1997             SEP-30-1997
<CASH>                                           2,385                   1,734                     473
<SECURITIES>                                     6,057                   5,992                   5,066
<RECEIVABLES>                                   10,987                   7,057                   8,990
<ALLOWANCES>                                       197                     188                     170
<INVENTORY>                                      9,393                  13,656                  14,082
<CURRENT-ASSETS>                                30,222                  29,385                  29,546
<PP&E>                                           7,739                   9,017                   9,505
<DEPRECIATION>                                   3,063                   3,479                   3,836
<TOTAL-ASSETS>                                  37,281                  37,589                  36,155
<CURRENT-LIABILITIES>                            6,170                   7,153                   7,345
<BONDS>                                            320                     278                     247
<PREFERRED-MANDATORY>                                0                       0                       0
<PREFERRED>                                          0                       0                       0
<COMMON>                                            53                      54                      54
<OTHER-SE>                                      29,606                  24,224                  24,471
<TOTAL-LIABILITY-AND-EQUITY>                    37,281                  37,589                  38,155
<SALES>                                          9,506                   5,076                   8,831
<TOTAL-REVENUES>                                 9,506                   5,075                   8,831
<CGS>                                            5,513                   3,242                   5,638
<TOTAL-COSTS>                                    5,513                   3,242                   5,638
<OTHER-EXPENSES>                                     0                       0                       0
<LOSS-PROVISION>                                    12                      16                       0
<INTEREST-EXPENSE>                                  11                      10                      16
<INCOME-PRETAX>                                  1,001                 (1,734)                     232
<INCOME-TAX>                                       340                   (595)                      81
<INCOME-CONTINUING>                                661                 (1,139)                     151
<DISCONTINUED>                                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                       661                 (1,139)                     151
<EPS-PRIMARY>                                     0.13                  (0.21)                    0.03
<EPS-DILUTED>                                     0.12                  (0.21)                    0.03


</TABLE>