CONSOLIDATED STATEMENTS OF OPERATIONS (in thousands, except per share amounts) (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
Net sales	$ 6,015	$ 4,785
Cost of goods sold	2,677	2,001
Gross margin	3,338	2,784
OPERATING EXPENSES:
Research and development	1,606	1,582
Selling, general and administrative	2,062	1,811
Total operating expenses	3,668	3,393
Operating income (loss)	(330)	(609)
NON-OPERATING INCOME:
Interest income	3	8
Foreign currency transaction gain (loss)	26	52
Total non-operating income (loss)	29	60
Income (loss) before income taxes	(301)	(549)
Income tax (expense) benefit	(32)	(5)
Net income (loss)	$ (333)	$ (554)
Basic earnings (loss) per share	$ (0.04)	$ (0.07)
Diluted earnings (loss) per share	$ (0.04)	$ (0.07)
Weighted-average basic shares (in thousands)	8,420	8,219
Weighted-average diluted shares (in thousands)	8,420	8,219

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 924
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-URI http://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a),(d))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227