Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net sales	$ 8,571,000	$ 7,690,000	$ 15,923,000	$ 15,761,000
Cost of sales	5,270,000	4,627,000	9,647,000	9,023,000
Gross profit	3,301,000	3,063,000	6,276,000	6,738,000
Operating expenses:
General and administrative	1,472,000	1,157,000	2,800,000	3,188,000
Sales and marketing	1,374,000	1,343,000	2,618,000	2,751,000
Research and development	173,000	154,000	308,000	341,000
Total operating expenses	3,019,000	2,654,000	5,726,000	6,280,000
Income from operations	282,000	409,000	550,000	458,000
Interest expense, net	(121,000)	(182,000)	(251,000)	(367,000)
Income before income taxes	161,000	227,000	299,000	91,000
Income tax expense (benefit)	6,000	(1,000)	6,000	(4,000)
Net income	$ 155,000	$ 228,000	$ 293,000	$ 95,000
Net income per share:
Basic (in dollars per share)	$ 0.03	$ 0.04	$ 0.05	$ 0.02
Diluted (in dollars per share)	$ 0.03	$ 0.04	$ 0.05	$ 0.02
Shares used in calculation of net income per share:
Basic (in shares)	6,054	5,965	6,042	5,942
Diluted (in shares)	6,163	5,973	6,147	5,963