CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2019	Jun. 29, 2018	Jun. 28, 2019	Jun. 29, 2018
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Sales	$ 8,006	$ 8,872	$ 15,171	$ 16,453
Cost of sales	(4,617)	(5,724)	(9,578)	(10,696)
Gross profit	3,389	3,148	5,593	5,757
Operating expenses:
Selling, general and administrative	(2,200)	(1,712)	(4,017)	(3,485)
Research and development	(834)	(753)	(1,736)	(1,520)
Pension	(56)	(54)	(113)	(108)
Total operating expenses	(3,090)	(2,519)	(5,866)	(5,113)
Operating income (loss)	299	629	(273)	644
Other expense, net	(77)	(100)	(148)	(175)
Income (loss) before income tax provision	222	529	(421)	469
Income tax provision	(19)	(20)	(19)	(31)
Net income (loss)	$ 203	$ 509	$ (440)	$ 438
Net income (loss) per common share -basic	$ 0.02	$ 0.04	$ (0.04)	$ 0.04
Net income (loss) per common share - diluted	$ 0.02	$ 0.04	$ (0.04)	$ 0.04
Weighted average common shares outstanding - basic	11,483	11,353	11,444	11,353
Weighted average common shares outstanding - diluted	11,895	12,050	11,887	11,997