Note 7 - Inventories, Net - Inventories (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Raw materials	$ 1,531,000	$ 1,249,000
Work in process	2,635,000	2,492,000
Finished goods	4,532,000	4,425,000
Allowance for excess quantities	(202,000)	(290,000)
Total inventories	$ 8,496,000	$ 7,876,000

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 after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(6))
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 55
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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

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Amount of valuation reserve for inventory.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
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-Section S99
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-Subparagraph (SAB TOPIC 5.BB)
-URI https://asc.fasb.org/extlink&oid=27011343&loc=d3e100047-122729

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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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