SELECTED FINANCIAL DATA                          
                                 (Unaudited)                                
                    (In thousands, except per share data)                   
                                                                            
                                                                            
Condensed Consolidated Statements of Operations Data:                       
                                                                            
                             Three Months Ended           Six Months Ended  
                      -------------------------------- ---------------------
                       6/30/2017  6/30/2016  3/31/2017  6/30/2017  6/30/2016
                      ---------- ---------- ---------- ---------- ----------
                                                                            
Net revenues          $   15,888 $   10,485 $   14,180 $   30,068 $   19,132
Gross margin               8,421      5,329      7,728     16,149      9,396
Operating expenses:                                                         
  Selling expense          1,871      1,471      1,668      3,539      2,806
  Engineering and                                                           
   product                                                                  
   development                                                              
   expense                   982        982        935      1,917      1,973
  General and                                                               
   administrative                                                           
   expense                 3,286      2,145      1,994      5,280      3,790
Operating income           2,282        731      3,131      5,413        827
Other income                  54         18         41         95         46
Earnings before                                                                             
  income  tax  expense                2,336                749            3,172            5,508                873
Income  tax  expense                      891                263            1,094            1,985                306
Net  earnings                              1,445                486            2,078            3,523                567
                                                                                                                                                        
Net  earnings  per                                                                                                                        
  share  -  basic                $          0.14  $          0.05  $          0.20  $          0.34  $          0.05
Weighted  average                                                                                                                        
  shares  outstanding  -                                                                                                              
  basic                                        10,277          10,296          10,265          10,271          10,343
                                                                                                                                                        
Net  earnings  per                                                                                                                        
  share  -  diluted            $          0.14  $          0.05  $          0.20  $          0.34  $          0.05
Weighted  average                                                                                                                        
  shares  outstanding  -                                                                                                              
  diluted                                    10,335          10,311          10,295          10,315          10,357
                                                                                                                                                        
                                                                                                                                                        
                                                                                                                                                        
Condensed  Consolidated  Balance  Sheets  Data:                                                                  
                                                                                                                                                        
                                                                                                                  As  of:                          
                                                                                        --------------------------------
                                                                                          6/30/2017    3/31/2017  12/31/2016
                                                                                        ----------  ----------  ----------
                                                                                                                                                        
Cash  and  cash  equivalents                                      $        7,596  $      27,455  $      28,611
Trade  accounts  receivable,  net                                    11,938            9,817            5,377
Inventories                                                                            6,212            3,921            3,676
Total  current  assets                                                        26,375          41,567          38,006
Net  property  and  equipment                                              1,525                934                944
Total  assets                                                                        56,704          46,353          42,844
Accounts  payable                                                                  2,823            1,833            1,368
Accrued  expenses                                                                  4,919            2,975            3,113
Total  current  liabilities                                                9,732            6,433            5,056
Noncurrent  liabilities                                                      5,354                    -                    -
Total  stockholders'  equity                                            41,618          39,920          37,788
                                                                                                                                                        
                                                                                                                                                        
                                                                                                                                                        
Condensed  Consolidated  Balance  Sheets  Data:                                                                  
                                                                                                                                                        
                                                                                                                  As  of:                          
                                                                                        --------------------------------
                                                                                          6/30/2017    3/31/2017  12/31/2016
                                                                                        ----------  ----------  ----------
                                                                                                                                                        
Cash  and  cash  equivalents                                      $        7,596  $      27,455  $      28,611
Trade  accounts  receivable,  net                                    11,938            9,817            5,377
Inventories                                                                            6,212            3,921            3,676
Total  current  assets                                                        26,375          41,567          38,006
Net  property  and  equipment                                              1,525                934                944
Total  assets                                                                        56,704          46,353          42,844
Accounts  payable                                                                  2,823            1,833            1,368
Accrued  expenses                                                                  4,919            2,975            3,113
Total  current  liabilities                                                9,732            6,433            5,056
Noncurrent  liabilities                                                      5,354                    -                    -
Total  stockholders'  equity                                            41,618          39,920          37,788