Balance sheet details - Inventories (Details) - USD ($)	Jun. 30, 2025	Dec. 31, 2024	Jun. 30, 2024
Details
Raw material	$ 2,205,157	$ 2,569,277
Work-in-process	2,036,744	1,605,994
Finished goods	2,657,397	2,864,549
Inventories, gross	6,899,298	7,039,820
Valuation allowance	(459,088)	(543,650)
Inventories, net	$ 6,440,210	$ 6,496,170	$ 6,937,695

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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