Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Statement of Cash Flows [Abstract]
Net income	$ 1,309,738	$ 600,057
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Deferred income taxes	175,453	(27,027)
Depreciation and amortization	95,904	125,120
Loss on sale of equipment	5,596	0
Non-cash lease expense	201,884	214,793
Forgiveness of PPP Loan	(722,577)	(722,577)
(Recovery of) provision for inventory obsolescence	(61,932)	25,000
Non-cash stock-based compensation	19,733	21,996
Changes in assets and liabilities:
Decrease (increase) in accounts receivable	884,281	(521,677)
Decrease (increase) in inventories	679,424	(370,310)
Decrease in prepaid expenses and other assets	19,027	189,889
(Decrease) increase in accounts payable	(499,660)	166,338
Increase in accrued legal damages	208,250	231,474
(Decrease) increase in deferred revenues	(74,231)	10,839
(Decrease) in accrued payroll, vacation pay & withholdings	(46,694)	(55,500)
(Decrease) in operating lease liabilities	(201,884)	(214,793)
(Decrease) increase in accrued expenses	(191,829)	70,762
Net cash provided by (used in) operating activities	1,800,483	(255,616)
Cash flows from investing activities:
Acquisition of equipment	(16,068)	(67,902)
Net cash used in investing activities	(16,068)	(67,902)
Cash flows from financing activities:
Payment of dividends	(320,000)	(80,000)
Proceeds from PPP loans	0	1,445,154
Repayment of line of credit	0	(680,000)
Repayment of capitalized lease obligations	0	(50)
Net cash (used in) provided by financing activities	(320,000)	685,104
Net increase in cash and restricted cash	1,464,415	361,586
	5,496,325	5,134,739
Supplemental cash flow information:
Interest paid	0	19,497
	6,960,740	5,496,325
Cash	3,485,275	3,126,195
Restricted cash	2,011,050	2,008,544
Cash	4,949,690	3,485,275
Restricted cash	$ 2,011,050	$ 2,011,050