Note 3 - Summary of Inventory (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Furnace parts and supplies	$ 466,538	$ 507,849
Raw materials	1,498,406	1,501,050
Work in process	1,770,070	1,326,840
Finished goods and filtration systems	1,788,161	2,028,225
Reserve for obsolescence	(606,504)	(449,098)
Net Inventory	$ 4,916,671	$ 4,914,866

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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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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

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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer.

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