Note 4 - Property and Equipment - Property and Equipment (Details) - USD ($)	Jun. 30, 2020	Mar. 31, 2020	Mar. 31, 2019
Machinery and equipment	$ 199,810		$ 199,810
Leasehold improvements	3,750		3,750
Property and equipment	203,560		203,560
Accumulated depreciation and amortization	(154,978)	$ (145,602)	(145,602)
Property and equipment, net	$ 48,582	$ 57,958	$ 57,958

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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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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