Note 4 - Inventory - Inventory (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Raw materials and component parts	$ 3,390,216	$ 3,904,865
Work-in-process	4,019,377	3,949,647
Finished products	9,776,688	9,183,532
Total inventory	17,186,281	17,038,044
Less: inventory reserves	436,070	452,607
Net inventory	$ 16,750,211	$ 16,585,437

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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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount of valuation reserve for inventory.

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

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