Note 4 - Inventory - Inventory (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Raw materials and component parts	$ 2,412,331	$ 2,313,664
Work-in-process	2,154,000	1,209,117
Finished products	1,840,123	2,201,693
Total inventory	6,406,454	5,724,474
Less: inventory reserves	242,342	226,492
Net inventory	$ 6,164,112	$ 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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