Note 4 - Inventories - Inventories (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Raw materials	$ 13,545,000	$ 9,729,000
Work in process	3,890,000	2,003,000
Finished goods	7,534,000	5,017,000
Total inventory	$ 24,969,000	$ 16,749,000

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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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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