Note 3 - Inventories - Schedule of Inventory (Details) - USD ($)	Jun. 30, 2024	Dec. 31, 2023
Raw material and common parts	$ 7,829,000	$ 7,828,000
Work-in-process	8,270,000	6,466,000
Finished goods	497,000	531,000
Inventory, Gross	16,596,000	14,825,000
Less inventory reserve	(766,000)	(627,000)
Total inventories	$ 15,830,000	$ 14,198,000

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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