Note 4 - Inventory - Inventory (Details) - USD ($)	Sep. 30, 2019	Dec. 31, 2018
Raw materials and component parts	$ 3,082,312	$ 2,313,664
Work-in-process	2,180,458	1,209,117
Finished products	2,158,350	2,201,693
Total inventory	7,421,120	5,724,474
Less: inventory reserves	321,447	226,492
Net inventory	$ 7,099,673	$ 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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