Note 4 - Inventory - Inventory (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Raw materials and component parts	$ 3,897,133	$ 2,945,427
Work-in-process	3,449,252	2,800,699
Finished products	3,999,920	2,183,170
Total Inventory	11,346,305	7,929,296
Less: Inventory reserves	315,345	250,606
Net Inventory	$ 11,030,960	$ 7,678,690

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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