STATEMENTS OF CASH FLOWS (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 268,098	$ 106,375
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	293,116	304,511
Amortization	2,175	2,156
Deferred income taxes	189,672	89,245
Stock-based compensation	24,261	27,480
Loss on disposal of fixed assets	36	288
Changes in:
Receivables	208,051	(83,290)
Inventory	158,478	(133,305)
Prepaid expenses and other assets	44,957	(66,403)
Accrued expenses	(43,486)	(98,618)
Accounts payable	(130,532)	41,138
Deferred revenue	0	(8,250)
Net cash provided by operating activities	1,014,826	181,327
CASH FLOWS FROM INVESTING ACTIVITES :
Purchase of property, plant and equipment	(120,136)	(249,571)
Maturities of short-term investments	2,240,000	3,183,000
Purchases of short-term investments	(2,738,000)	(2,240,000)
Net cash (used for) provided by investing activities	(618,136)	693,429
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt principal repayments	(135,047)	(128,610)
Proceeds from exercise of stock options	0	50,800
Tax benefits related to stock options	0	6,842
Net cash used for financing activities	(135,047)	(70,968)
NET INCREASE IN CASH AND CASH EQUIVALENTS	261,643	803,788
BEGINNING CASH AND CASH EQUIVALENTS	2,673,719	781,516
ENDING CASH AND CASH EQUIVALENTS	2,935,362	1,585,304
INCOME TAXES PAID	0	(605)
INTEREST EXPENSE PAID	(51,118)	(57,637)
NON-CASH ACTIVITIES:
Change in capital expenditures included in accounts payable	68,100	(25,762)
Net change in fair value of interest rate swap	$ (24,279)	$ 12,521