Note 4 - Inventories - Components of Inventories (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Raw materials	$ 1,030,955	$ 928,221
Work-in-process	194,060	195,618
Inventories	$ 1,225,015	$ 1,123,839

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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