1、Smart Design: Battery box with battery quick connector and 50A fuse, 12V power outlet, digital voltmeter display, dual USB socket, circuit breaker switch, versatile and practical. 2、High Performance: Outdoor car 12V portable battery box with USB port and voltmeter, professional design and stable performance bring you an excellent using experience. 3、Weatherproof Box: The upgraded smart battery box is windproof, rainproof and dustproof, and able to be used in various harsh environmental conditions. 4、Impact Resistant: Battery box is made of high strength ABS housing, which enables the box to withstand shock and is not affected by gases, oils, and UV rays. 5、Wide Application: The battery box with circuit breaker can be safely and easily connected to the battery port without opening the box, widely used in RV, SUV, ATV camper, truck, motorcycles.