Note 4 - Inventory - Inventory (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Raw materials and component parts	$ 1,170,772	$ 2,637,138
Work-in-process		523,644
Finished products	954,491	1,200,204
Total Inventory	2,152,263	4,360,986
Less: inventory reserves	144,767	457,505
Net Inventory	$ 1,980,496	$ 3,903,481

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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