Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	6 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 644,445	$ 760,872
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Loss on disposal of equipment	541	875
Change in accounts receivable and inventory reserves	16,457	35,760
Depreciation and amortization	207,714	116,711
Change in cash surrender value of life insurance	(34,002)	(34,002)
Warranty reserve	99,186	200,245
Compensation expense related to stock options	1,000	1,469
Change in operating assets and liabilities:
Accounts receivable	644,815	(519,568)
Notes receivable and other non-trade receivables	212,676	128,340
Inventories	600,677	(1,204,781)
Prepaid expenses and other	304,460	(113,093)
Accounts payable	(1,878,760)	460,839
Accrued expenses	(363,224)	(412,785)
Income taxes receivable/ payable	315,000	(596,890)
Total adjustments	126,540	(1,936,880)
Net cash provided by (used in) operating activities	770,985	(1,176,008)
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from sale of investments		51,035
Capital expenditures	(220,606)	(605,709)
Proceeds from sale of assets	3,500
Net cash used in investing activities	(217,106)	(554,674)
CASH FLOWS FROM FINANCING ACTIVITIES:
Payment of cash dividend	(611,571)	(611,571)
Payment on capital leases		(6,496)
Proceeds from exercise of stock options		124,350
Net cash used in financing activities	(611,571)	(493,717)
NET DECREASE IN CASH AND CASH EQUIVALENTS	(57,692)	(2,224,399)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	5,814,184	6,515,067
CASH AND CASH EQUIVALENTS AT END OF PERIOD	5,756,492	4,290,668
Cash paid during the period for:
Interest	17,000	2,000
Income taxes	$ 46,000	$ 1,027,000