Inventory

3 Months Ended

Mar. 31, 2021

Inventory Disclosure [Abstract]

Inventory

Inventory

Inventory consists of the following as of the dates presented (in thousands):

			December 31,
	March 31, 2021		2020		2019
Raw materials	$	626	$	633	$	412
Work in process	1,054		350		258
Finished goods	543		644		320
Total	$	2,223	$	1,627	$	990

An inventory write-off of $7 thousand and $169 thousand was recorded for the three months ended March 31, 2021 and 2020 (unaudited), respectively, and $435 thousand and $155 thousand was recorded for the years ended December 31, 2020 and 2019, respectively.