Note 3 - Inventories: Schedule of Inventory, Current (Details) - USD ($)	Jan. 31, 2018	Apr. 30, 2017
Details
Inventory, Raw Materials, Gross	$ 7,406,466	$ 4,087,036
Inventory, Work in Process, Gross	1,740,132	1,802,782
Inventory, Finished Goods, Gross	3,138,089	3,089,703
Inventory, Gross	12,284,687	8,979,521
Reserve for obsolete inventory	(178,776)	(163,048)
Inventories, net	$ 12,105,911	$ 8,816,473

Represents the monetary amount of Reserve for obsolete inventory, as of the indicated date.

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- Definition

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

+ References

+ Details

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- Definition

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.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=68049868&loc=d3e3927-108312

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765

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- Definition

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

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- Definition

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.

+ References

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