Inventories (Details) - USD ($) $ in Thousands	Mar. 30, 2019	Dec. 29, 2018
Summary of inventories
Raw materials	$ 38,285	$ 39,086
Work in process	29,605	26,871
Finished goods	26,120	23,963
Provision for obsolete and slow moving inventory	(5,114)	(3,931)
Total	$ 88,896	$ 85,989

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 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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