Related Party Transactions/Activity (Details Narrative) - USD ($)	6 Months Ended
Nov. 30, 2017	Nov. 30, 2016
Green Plastic Pallets [Member]
Sales	$ 256,819	$ 146,885
Account receivable	73,027
Yorktown Management & Financial Services, LLC [Member]
Payments of rental fees	742,500	715,000
Operating lease rental fees	4,000
TriEnda Holdings, LLC [Member]
Sales	0	368,690
Scrap material purchase amount	45,467	$ 24,265
Yorktown's Grinding Equipment [Member]
Payments of rental fees	22,500
Yorktown's Pelletizing Equipment [Member]
Payments of rental fees	$ 5,000

For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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