Note 4 - Inventory - Inventory (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Raw materials and component parts	$ 1,987,221	$ 2,313,664
Work-in-process	1,736,430	1,209,117
Finished products	1,893,087	2,201,693
Total inventory	5,616,738	5,724,474
Less: inventory reserves	281,744	226,492
Net inventory	$ 5,334,994	$ 5,497,982

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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