5. INVENTORIES

Inventory costs include materials, labor and factory overhead. Inventories are stated at the lower of cost or net realizable value, determined on a first-in, first-out basis. Appropriate consideration is given to obsolescence, valuation and other factors in determining net realizable value. Revisions of these estimates could result in the need for adjustments. Inventories, net of reserves, at March 31, 2019 and December 31, 2018 consisted of the following:


	March 31,		December 31,
	2019		2018
Chassis	$	7,588	$	8,921
Raw materials		40,393		40,021
Work in process		17,653		14,995
Finished goods		30,522		29,830
	$	96,156	$	93,767