Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Net sales	$ 7,504,000	$ 10,044,000	$ 23,265,000	$ 24,143,000
Cost of sales	4,627,000	5,928,000	13,650,000	15,906,000
Gross profit	2,877,000	4,116,000	9,615,000	8,237,000
Operating expenses:
General and administrative	958,000	1,337,000	4,146,000	4,190,000
Sales and marketing	1,406,000	2,068,000	4,157,000	5,088,000
Research and development	146,000	216,000	487,000	635,000
Total operating expenses	2,510,000	3,621,000	8,790,000	9,913,000
Income (loss) from operations	367,000	495,000	825,000	(1,676,000)
Interest expense, net	(164,000)	(134,000)	(530,000)	(414,000)
Income (loss) before income taxes	203,000	361,000	295,000	(2,090,000)
Income tax expense	32,000	73,000	29,000	33,000
Net income (loss)	$ 171,000	$ 288,000	$ 266,000	$ (2,123,000)
Net income (loss) per share:
Basic (in dollars per share)	$ 0.03	$ 0.05	$ 0.04	$ (0.37)
Diluted (in dollars per share)	$ 0.03	$ 0.05	$ 0.04	$ (0.37)
Shares used in calculation of net income (loss) per share:
Basic (in shares)	5,957	5,836	5,946	5,809
Diluted (in shares)	5,962	5,862	5,949	5,809