Inventories (Details) - USD ($)	Mar. 31, 2024	Dec. 31, 2023
Inventories
Raw material and common parts	$ 7,760,000	$ 7,828,000
Work-in-process	7,416,000	6,466,000
Finished goods	378,000	491,000
Inventory, Gross	15,554,000	14,785,000
Less inventory reserve	(625,000)	(587,000)
Total inventories	$ 14,929,000	$ 14,198,000

No definition available.

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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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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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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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