Inventories are valued at the lower of cost (determined using the

first-in,

first-out

method) or net realizable value. Fixed production overhead is allocated to the inventory cost per unit based on the normal capacity of the production facilities. Abnormal production costs, including fixed cost variances from normal production capacity, if any, are charged to cost of revenues in the period incurred. All shipping, handling and customs (e.g., tariff) costs incurred in connection with the sale of products are included in cost of revenues.

Inventory that is estimated to be excess, obsolete or unmarketable is written down to net realizable value. The Company’s estimation process for assessing net realizable value is based upon management’s estimate of expected future utility which is derived based on backlog, historical consumption and expected market conditions. If the Company’s estimated demand and/or market expectation were to change or if product sales were to decline, the Company’s estimation process may cause larger inventory reserves to be recorded, resulting in larger charges to cost of revenues.

Inventories were as follows (in thousands):


	June 30, 2021		December 31, 2020
Raw materials	$	42,530	$	42,556
Work-in-process		10,101		7,424
Finished goods		4,498		7,289

	$	57,129	$	57,269