6. BALANCE SHEET DETAIL (Details 1) - USD ($) $ in Thousands	May 31, 2019	May 31, 2018
Property, Plant and Equipment, Net [Abstract]
Leasehold improvements	$ 1,154	$ 1,154
Furniture and fixtures	983	984
Machinery and equipment	3,097	2,865
Test equipment	2,604	2,595
Property and equipment, gross	7,838	7,598
Less: Accumulated depreciation and amortization	(6,793)	(6,395)
Property and equipment, net	$ 1,045	$ 1,203

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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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale.

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