Note 4 - Equipment and Leasehold Improvements (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Property, Plant and Equipment [Table Text Block]

	Year Ended December 31,
	2021			2020			Estimated Useful Life (in years)
Machinery and equipment	$	6,270,000		$	6,004,000		2.5	-	10
Computer and software		631,000			631,000		2	-	5
Office equipment		256,000			256,000		5	-	10
Leasehold improvements		932,000			932,000		5 years or remaining lease term
Total equipment		8,089,000			7,823,000
Less accumulated depreciation		(6,828,000	)		(6,399,000	)
Total equipment and leasehold improvements, net	$	1,261,000		$	1,424,000