Note 4 - Inventory - Inventory (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Raw materials and component parts	$ 3,914,652	$ 3,897,133
Work-in-process	3,963,814	3,449,252
Finished products	5,556,355	3,999,920
Total inventory	13,434,821	11,346,305
Less: inventory reserves	315,345	315,345
Net inventory	$ 13,119,476	$ 11,030,960

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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