Note 4 - Inventories - Summary of Inventories (Details) - USD ($)	Mar. 31, 2022	Mar. 31, 2021
Raw materials	$ 987,062	$ 660,678
Work in process	3,355,838	2,220,723
Finished goods	745,735	1,019,376
Total inventories	$ 5,088,635	$ 3,900,777

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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