Inventories (Details) - USD ($) $ in Thousands	Apr. 03, 2021	Jan. 02, 2021
Summary of inventories
Raw materials	$ 58,133	$ 49,361
Work in process	33,169	30,675
Finished goods	38,014	39,332
Provision for obsolete and slow moving inventory	(9,553)	(8,996)
Total	$ 119,763	$ 110,372

Summary of inventories.

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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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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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