Significant Accounting Policies (Details) - Inventories - USD ($)	Feb. 28, 2018	May 31, 2017
Inventories [Abstract]
Raw materials	$ 892,000	$ 830,000
Work in progress	891,000	728,000
Finished products	171,000	171,000
Total	$ 1,953,655	$ 1,729,121

No definition available.

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- Definition

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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-Topic 330
-SubTopic 10
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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.

+ References

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- Definition

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.

+ References

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