Note 4 - Inventory - Inventory (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
Raw materials and component parts	$ 2,547,745	$ 2,637,138
Work-in-process	641,430	523,644
Finished products	1,182,683	1,200,204
Total Inventory	4,371,858	4,360,986
Less: inventory reserves	465,917	457,505
Net Inventory	$ 3,905,941	$ 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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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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