Note 3 - Inventories - Schedule of Inventory (Details) - USD ($)	Mar. 31, 2025	Dec. 31, 2024
Raw material and common parts	$ 8,192,000	$ 8,044,000
Work-in-process	7,164,000	7,072,000
Finished goods	884,000	1,468,000
Inventory, Gross	16,240,000	16,584,000
Less inventory reserve	(752,000)	(758,000)
Inventories, net	$ 15,488,000	$ 15,826,000

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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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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