Inventories (Details) - USD ($) $ in Thousands	Sep. 28, 2019	Dec. 29, 2018
Summary of inventories
Raw materials	$ 37,869	$ 39,086
Work in process	28,752	26,871
Finished goods	29,945	23,963
Provision for obsolete and slow moving inventory	(7,228)	(3,931)
Total	$ 89,338	$ 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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