Note 4 - Inventory - Inventory (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Raw materials and component parts	$ 4,634,164	$ 3,897,133
Work-in-process	4,297,343	3,449,252
Finished products	6,859,877	3,999,920
Total inventory	15,791,384	11,346,305
Less: inventory reserves	376,434	315,345
Net inventory	$ 15,414,950	$ 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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