Note 1 - Summary of Significant Accounting Policies - Major Components of Inventories (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Raw materials	$ 1,323,655	$ 1,667,154
Work-in-progress	428,753	419,906
Finished goods	1,065,458	1,449,854
Reduction to LIFO cost	(1,172,891)	(1,356,378)
Total Inventories	$ 1,644,975	$ 2,180,536

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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