Note 4 - Inventory - Inventory (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Raw materials and component parts	$ 3,038,993	$ 2,945,427
Work-in-process	3,403,158	2,800,699
Finished products	4,037,811	2,183,170
Total inventory	10,479,962	7,929,296
Less: inventory reserves	250,939	250,606
Net inventory	$ 10,229,023	$ 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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