XML 39 R29.htm IDEA: XBRL DOCUMENT v3.21.2
Inventories (Details) - USD ($)
Jun. 30, 2021
Dec. 31, 2020
Inventory Disclosure [Abstract]    
Raw materials and sub-assemblies $ 4,429,107 $ 3,642,377
Finished goods 396,346 281,104
Inventory reserves (805,943) (727,639)
Inventory, net $ 4,019,510 $ 3,195,842