Note 5 - Inventories, Net - Components of Inventories (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Raw materials	$ 1,701,667	$ 2,016,488
Work-in-process	590,999	205,385
Finished goods
Gross inventories	2,292,666	2,221,873
Less reserve for obsolescence	(410,000)	(360,000)
Inventories, net	$ 1,882,666	$ 1,861,873

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 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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