Condensed Consolidated Balance Sheet Components

Property and Equipment, Net

Property and equipment, net consisted of the following:



	June 30, 2019			December 31, 2018
	(unaudited)
	(in thousands)
Machinery and equipment	$	26,264		$	23,440
Computer hardware	5,528			4,949
Leasehold improvements	14,736			13,965
Furniture and fixtures	1,549			1,522
Computer software	741			643
Construction in progress	4,358			3,118
Property and equipment, gross	53,176			47,637
Less: accumulated depreciation and amortization	(18,365		)	(16,634		)
Property and equipment, net	$	34,811		$	31,003

Depreciation and amortization expense related to property and equipment was $2.2 million and $1.3 million for the three months ended June 30, 2019 and 2018, respectively, and $4.3 million and $2.5 million for the six months ended June 30, 2019 and 2018, respectively.

As of June 30, 2019 and December 31, 2018, total property and equipment financed under capital leases was $346,000 and $504,000, net of accumulated amortization of $187,000 and $294,000, respectively. Amortization expense related to total property and equipment financed under capital leases was $21,000 and $41,000 for the three months ended June 30, 2019 and 2018, respectively, and $51,000 and $105,000 for the six months ended June 30, 2019 and 2018, respectively.

Accrued Expenses

Accrued expenses consisted of the following:



	June 30, 2019		December 31, 2018
	(unaudited)
	(in thousands)
Accrued royalty obligations	$	1,324	$	707
Accrued legal expenses	1,610		814
Accrued tax liabilities	1,713		1,470
Accrued professional services	1,783		1,791
Purchases of property and equipment included in accrued expenses	1,417		343
Other	3,245		1,956
Total accrued expenses	$	11,092	$	7,081