Condensed Balance Sheets (Current Period Unaudited) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
CURRENT ASSETS:
Cash and cash equivalents	$ 617,246	$ 1,623,137
Short-term investments	2,940,000	2,695,000
Trade receivables, less allowance of $112,000 in 2019 and $53,000 in 2018	1,821,114	2,215,215
Inventories	2,840,176	2,046,588
Prepaid expenses and other assets	259,839	375,362
Income taxes receivable	113,321	2,768
Total current assets	8,591,696	8,958,070
PROPERTY, PLANT, AND EQUIPMENT, at cost:
Land and building	9,500,429	9,500,429
Machinery and equipment	5,022,691	4,964,816
Office equipment	1,564,978	1,559,728
Vehicles	245,674	245,679
Property, plant, and equipment, Gross	16,333,772	16,270,652
Less accumulated depreciation	(8,298,897)	(8,185,910)
Total property, plant and equipment at cost, net	8,034,875	8,084,742
INTANGIBLE ASSETS, less accumulated amortization of $155,908 in 2019 and $149,740 in 2018	372,693	376,406
Total assets	16,999,264	17,419,218
CURRENT LIABILITIES
Current portion of long-term debt	129,582	129,282
Accounts payable	860,106	647,528
Accrued compensation	236,935	366,900
Other accrued liabilities	143,019	159,821
Total current liabilities	1,369,642	1,303,531
LONG-TERM LIABILTIES
Long-term debt, less current portion	2,788,703	2,821,657
Deferred income taxes	183,000	183,000
Total long-term liabilities	2,971,703	3,004,657
Total liabilities	4,341,345	4,308,188
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY
Preferred stock, par value $.10 per share; authorized 250,000 shares; issued none
Common stock, par value $.10 per share; authorized 4,750,000 shares; issued and outstanding 1,983,553 shares in 2019 and 2018.	198,355	198,355
Additional paid-in-capital	2,724,944	2,723,024
Retained earnings	9,734,620	10,189,651
Total stockholders' equity	12,657,919	13,111,030
Total liabilities and stockholders' equity	$ 16,999,264	$ 17,419,218