Quarterly report pursuant to Section 13 or 15(d)

Inventories (Details)

v3.8.0.1
Inventories (Details) - USD ($)
Mar. 31, 2018
Dec. 31, 2017
Inventories    
Finished goods $ 6,151,713 $ 5,489,360
Work in process 464,392 470,187
Raw materials 1,436,825 1,356,395
Inventories 8,052,930 7,315,942
Inventory valuation reserves $ 843,000 $ 812,000