Note 4 - Inventories, Net - Components of Inventories (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Raw materials	$ 928,221	$ 1,281,250
Work-in-process	195,618	428,463
Inventories	$ 1,123,839	$ 1,709,713

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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
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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.

+ References

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-Publisher FASB
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-Topic 210
-SubTopic 10
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