Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 1,277,205	$ 1,339,600
Loss (gain) on disposal of equipment	2,184	(29,659)
Change in accounts receivable and inventory reserves	(19,293)	45,936
Depreciation and amortization	312,843	191,703
Change in cash surrender value of life insurance	(51,003)	(51,003)
Deferred income taxes		116,000
Warranty reserve	153,493	361,757
Compensation expense related to stock options	7,000	1,469
Change in operating assets and liabilities:
Accounts receivable	450,284	748,252
Notes receivable and other non-trade receivables	208,873	134,900
Inventories	1,111,491	(46,548)
Prepaid expenses and other	234,341	(264,651)
Accounts payable	(190,899)	(812,839)
Accrued expenses	487,210	197,778
Income taxes receivable/ payable	636,200	(430,843)
Total adjustments	3,342,724	162,252
Net cash provided by operating activities	4,619,929	1,501,852
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from sale of investments		51,035
Capital expenditures	(292,513)	(749,772)
Proceeds from sale of assets	8,000	37,500
Net cash used in investing activities	(284,513)	(661,237)
CASH FLOWS FROM FINANCING ACTIVITIES:
Payment of cash dividend	(611,571)	(611,571)
Payment on capital leases		(8,271)
Proceeds from exercise of stock options		124,350
Net cash used in financing activities	(611,571)	(495,492)
NET DECREASE IN CASH AND CASH EQUIVALENTS	3,723,845	345,123
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	5,814,184	6,515,067
CASH AND CASH EQUIVALENTS AT END OF PERIOD	9,538,029	6,860,190
Cash paid during the period for:
Interest	17,000	1,800
Income taxes	$ 82,000	$ 1,073,000