Battery CHARGER, an electrical device supplied with alternating current, which produces a directcurrentoutput for charging the battery on the airplane.
It has glow caution light, nightlight, directcurrentoutput function that could emergency charging for mobile phone, digital goods and so on and has FM radio function.
The tester is additionally connected with a filament switching indicator and a pair of directcurrentoutput poles for testing the condition of the filament of a fluorescent lamp.