Inventories (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Inventories
Raw materials	$ 4,336,000	$ 4,251,000
Work in progress	132,000	133,000
Finished goods	42,272,000	45,252,000
Subtotal	46,740,000	49,636,000
Less inventory reserve	(675,000)	(675,000)
Total inventories	$ 46,065,000	$ 48,961,000

Amount of inventory reserves for last-in first-out (LIFO) and other inventory valuation methods.

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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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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 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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