Note 3 - Inventories - Major Components of Inventories (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Raw materials	$ 2,127,147	$ 1,767,458
Work-in-progress	393,802	370,075
Finished goods	1,632,673	1,196,516
Reduction to LIFO cost	(1,313,446)	(1,287,461)
Total Inventories	$ 2,840,176	$ 2,046,588

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 by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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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 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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