Inventories (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
Inventories
Finished goods	$ 6,151,713	$ 5,489,360
Work in process	464,392	470,187
Raw materials	1,436,825	1,356,395
Inventories	8,052,930	7,315,942
Inventory valuation reserves	$ 843,000	$ 812,000

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

+ References

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- Definition

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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- Definition

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Amount of valuation reserve for inventory.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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