Inventories: Inventories (Details) - USD ($)	Mar. 31, 2023	Dec. 31, 2022
Details
Raw material	$ 4,609,907	$ 4,460,071
Work-in-process	3,147,846	2,747,427
Finished goods	2,862,199	2,534,732
Inventories, gross	10,619,952	9,742,230
Valuation reserves	(621,000)	(621,000)
Inventories, net	$ 9,998,952	$ 9,121,230

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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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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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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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount of valuation reserve for inventory.

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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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