INVENTORIES (Details) - USD ($) $ in Thousands	Apr. 03, 2021	Dec. 31, 2020
Inventory at FIFO
Finished products	$ 2,905	$ 2,878
Materials and work in process	77,310	77,609
Gross inventories	80,215	80,487
Less: LIFO reserve	(48,465)	(48,016)
Less: excess and obsolescence reserve	(2,996)	(3,394)
Net inventories	$ 28,754	$ 29,077

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 by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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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 of valuation reserve for inventory.

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The aggregate carrying amount as of the balance sheet date of items held by the entity which are partially completed at the time of measurement and unprocessed items that will go through the production process and become part of the final product. Includes supplies used directly or indirectly in the manufacturing or production process. This element may be used when the reporting entity combines work in process and raw materials into an aggregate amount.

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