Balance Sheet Components

12 Months Ended

Dec. 31, 2018

Property and Equipment, net (in thousands):



	December 31,			December 31,
	2018			2017
Machinery and equipment	$	3,785		$	3,428
Construction in progress	730			879
Computer and office equipment	407			310
Leasehold improvements	448			272
Furniture and fixtures	148			29
	5,518			4,918
Less: Accumulated depreciation and amortization	(3,364		)	(3,022		)
	$	2,154		$	1,896

Depreciation expense was $0.7 million and $1.0 million for the years ended December 31, 2018 and 2017, respectively.

Accrued Liabilities and Other (in thousands):



	December 31,		December 31,
	2018		2017
Accrued compensation and related expenses	$	5,425	$	3,732
Accrued interest	—		831
Accrued professional services	583		341
Sales tax payable	388		466
Liability for early exercise of unvested stock options	331		65
Sales and warranty reserves	35		149
Other	98		140
	$	6,860	$	5,724