Condensed Consolidated Statements of Income - USD ($)	3 Months Ended
	Aug. 31, 2021	Aug. 31, 2020
Income Statement [Abstract]
Sales, net	$ 7,307,737	$ 5,759,457
Cost of goods sold	5,717,498	4,204,889
Gross profit	1,590,239	1,554,568
Selling, general and administrative expenses	1,472,099	1,363,203
Operating income	118,140	191,365
Other income, net	63,737	9,646
Income before provision for income taxes	181,877	201,011
Provision for income taxes	0	25,000
Net income	$ 181,877	$ 176,011
Basic and diluted earnings per common share	$ 0.05	$ 0.05