Note 2 - Inventories - Major Components of Inventories (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Raw materials	$ 1,286,151	$ 1,323,655
Work-in-progress	399,738	428,753
Finished goods	1,140,543	1,065,458
Reduction to LIFO cost	(1,218,604)	(1,172,891)
Total Inventories	$ 1,607,828	$ 1,644,975

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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