Inventories are stated at the lower of cost or net realizable value on a first-in, first-out basis and are comprised of the following (in thousands):

	September 30, 2022		December 31, 2021
Raw materials	$	2,195	$	1,591
Work-in-process		1,231		953
Finished goods		816		1,365
Total inventories, net	$	4,242	$	3,909

	September 30, 2022			December 31, 2021
Office and computer equipment	$	749		$	749
Software		783			783
Laboratory equipment		5,573			5,507
Furniture		197			197
Manufacturing equipment		1,445			1,445
Manufacturing tooling and molds		478			478
T2-owned instruments and components		7,150			6,668
Leasehold improvements		3,785			3,768
Construction in progress		774			512
		20,934			20,107
Less accumulated depreciation and amortization		(16,200	)		(15,432	)
Property and equipment, net	$	4,734		$	4,675

Construction in progress is primarily comprised of equipment that has not been placed in service. T2-owned instruments and components is comprised of raw materials and work-in-process inventory that are expected to be used or used to produce T2-owned instruments, based on the Company’s business model and forecast, and completed instruments that will be used for internal research and development, clinical studies or reagent rental agreements with customers. At September 30, 2022, there was $1.0 million of raw materials or work-in-process inventory in T2-owned instruments and components compared with $1.4 million at December 31, 2021. Completed T2-owned instruments are placed in service once installation procedures are completed and are depreciated over five years. Depreciation expense for T2-owned instruments placed at customer sites pursuant to reagent rental agreements is recorded as a component of cost of product revenue and was immaterial for the three months ended September 30, 2022 and 2021. Depreciation expense for T2-owned instruments placed at customer sites pursuant to reagent rental agreements is recorded as a component of cost of product revenue and was $0.1 million for the nine months ended September 30, 2022 and 2021.

Depreciation expense for T2-owned instruments used for internal research and development and clinical studies is recorded as a component of research and development expense. Depreciation and amortization expense of $0.3 million and $0.3 million was charged to operations for the three months ended September 30, 2022 and 2021, respectively. Depreciation and amortization expense of $0.8 million and $1.0 million was charged to operations for the nine months ended September 30, 2022 and 2021, respectively.

	September 30, 2022		December 31, 2021
Accrued payroll and compensation	$	3,894	$	3,687
Accrued research and development expenses		1,482		1,250
Accrued professional services		392		384
Accrued interest		1,000		974
Operating lease liabilities		1,295		1,174
Other accrued expenses		468		869
Total accrued expenses and other current liabilities	$	8,531	$	8,338