CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
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Sales	$ 27,716	$ 37,193
Cost of sales	(18,357)	(23,748)
Gross profit	9,359	13,445
Operating expenses:
Selling, general and administrative	(7,450)	(6,669)
Research and development	(3,164)	(2,903)
Pension	(226)	(217)
Total operating expenses	(10,840)	(9,789)
Operating income (loss)	(1,481)	3,656
Other income, net	(256)	(327)
Income (loss) before income tax provision	(1,737)	3,329
Income tax benefit (provision)	138	(21)
Net income (loss)	$ (1,599)	$ 3,308
Net income (loss) per common share - basic	$ (0.14)	$ 0.29
Net income (loss) per common share - diluted	$ (0.14)	$ 0.28
Weighted average common shares outstanding - basic	11,464	11,353
Weighted average common shares outstanding - diluted	11,464	12,002
Comprehensive income (loss), net of tax:
Net income (loss)	$ (1,599)	$ 3,308
Decrease (increase) in minimum pension liability	(206)	200
Total comprehensive income (loss)	$ (1,805)	$ 3,508