BALANCE SHEET COMPONENTS (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment, Gross	$ 2,281	$ 1,202
Less accumulated depreciation	(1,462)	(1,014)
Property and Equipment, Net	819	188
Assets acquired under capital lease:
Original book value	461	461
Accumulated depreciation	(441)	(379)
Net book value	20	82
Office furniture and equipment
Property, Plant and Equipment, Gross	1,172	998
Assembly equipment
Property, Plant and Equipment, Gross	128	128
Vehicles
Property, Plant and Equipment, Gross	184	76
Leasehold improvements
Property, Plant and Equipment, Gross	480	0
Leased devices
Property, Plant and Equipment, Gross	$ 317	$ 0

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 leased physical assets used in the normal conduct of business to produce goods and services.

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