NOTE 2 – DETAILS OF CERTAIN FINANCIAL STATEMENT COMPONENTS

Inventories, stated at the lower of cost or net realizable value, consisted of the following:


	March 31,		December 31,
	2021		2020
Inventories	(in thousands)
Raw materials	$	555	$	520
Work-in-process		229		246
Finished goods		97		100
Total inventories	$	881	$	866

Property, plant and equipment, net, consisted of the following:


	March 31,		December 31,
	2021		2020
Property, plant and equipment, net	(in thousands)
Furniture, machinery and equipment	$	1,661	$	1,662
Leasehold improvements		544		538
		2,205		2,200
Less: accumulated depreciation		(1,841)		(1,793)
Total property, plant and equipment, net	$	364	$	407

Depreciation expense totaled $54 thousand and $59 thousand for the three months ended March 31, 2021 and 2020, respectively.

Intangible assets, net consisted of the following:


	March 31,		December 31,
	2021		2020
Intangible assets, net	(in thousands)
Patents and trademarks	$	658	$	658
Less: accumulated amortization		(479)		(463)
Total intangible assets, net	$	179	$	195

Amortization expense totaled $17 thousand and $13 thousand for the three months ended March 31, 2021 and 2020, respectively. Future amortization expense on existing intangible assets over the next five years is as follows:


Years ending December 31,	(in thousands)
2021 (remainder of year)	$	49
2022		54
2023		42
2024		27
2025		7
Thereafter		—
	$	179

Accrued liabilities consisted of the following:


	March 31,		December 31,
	2021		2020
Accrued liabilities	(in thousands)
Accrued warranty	$	7	$	7
Accrued wages and benefits		138		180
Accrued vacation		103		110
Accrued other		47		46
Total accrued liabilities	$	295	$	343