Consolidated Statements of Operations and Comprehensive (Loss) Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Net sales	$ 21,707	$ 23,283
Cost of goods sold	13,288	14,347
Gross profit	8,419	8,936
Operating expenses:
Selling expenses	2,461	2,492
General and administrative	4,236	3,529
Research and development	2,576	2,452
Total operating expenses	9,273	8,473
(Loss) earnings from operations	(854)	463
Other expense:
Interest expense, net	(562)	(723)
Change in derivative liability		(142)
Total other expense	(562)	(865)
Loss before income taxes	(1,416)	(402)
Benefit for income taxes	(77)	(18)
Net loss	$ (1,339)	$ (384)
Net loss per share, basic and diluted	$ (0.15)	$ (0.05)
Weighted average shares outstanding, basic and diluted	8,899	8,189
Statements of Comprehensive (Loss) Income
Net loss	$ (1,339)	$ (384)
Changes in accumulated unrealized pension losses, net of taxes	22	424
Comprehensive (loss) income	$ (1,317)	$ 40