Note 4 - Property and Equipment - Property and Equipment (Details) - USD ($)	Jun. 30, 2021	Mar. 31, 2021
Machinery and equipment	$ 199,810	$ 199,810
Leasehold improvements	3,750	3,750
Property and equipment	203,560	203,560
Accumulated depreciation and amortization	(189,055)	(181,289)
Property and equipment, net	$ 14,505	$ 22,271

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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