Note 3 - Inventories - Summary of Inventories (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Raw materials	$ 656,525	$ 629,090
Work-in-process	317,494	339,746
Finished goods	674,735	482,972
Inventory allowance	(9,712)	(12,794)
Inventory, net	$ 1,639,042	$ 1,439,014

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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