Note 4 - Inventory - Inventory (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Raw materials and component parts	$ 2,945,427	$ 2,313,664
Work-in-process	2,800,699	1,209,117
Finished products	2,183,170	2,201,693
Total Inventory	7,929,296	5,724,474
Less: Inventory reserves	250,606	226,492
Net Inventory	$ 7,678,690	$ 5,497,982

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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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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