Inventories (Details) - USD ($) $ in Thousands	Jan. 02, 2021	Dec. 28, 2019
Summary of inventories
Raw materials	$ 49,361	$ 34,340
Work in process	30,675	28,667
Finished goods	39,332	29,711
Provision for obsolete and slow moving inventory	(8,996)	(7,523)
Total	$ 110,372	$ 85,195

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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