Note 5 - Inventories, Net - Components of Inventories (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Raw materials	$ 1,081,709	$ 928,221
Work-in-process	215,493	195,618
Inventories	$ 1,297,202	$ 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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