Note 4 - Inventories (Tables)

12 Months Ended

Dec. 31, 2017

Notes Tables

Schedule of Inventory, Current [Table Text Block]

	December 31,
	2017		2016
Raw materials	$	4,567,000	$	4,313,000
Work in process		1,058,000		2,535,000
Finished goods		4,624,000		4,146,000
	$	10,249,000	$	10,994,000