Double USB socket. With 5A fuse inside. Overcurrent protection, short-circuit protection, overvoltage protection, over discharge protection, overcharge protection, overheat protection. Waterproof socket and USB connection and integration. Product installation unique design. Separate USB waterproof cover. Applicable models: Motorcycle, ATV, Cross bike, Scooters and so on. Application: For most phones, GPS or any other device using USB power. It can be used for MP3 player, USB charging portable devices,GPS, iPhone, and other similar devices. Specification: Material: Plastic+Metal. Product Color: Black. Voltmeter Indicator light color: Red. Input voltage: DC 12V-24V. Voltage detection range: DC 8-28V. Voltage is displayed only by DC 12V-24V, other range of voltage will not be displayed. USB Output: DC 5V 3.1A (2.1A+1A). Black Wire: Negative. Red Wire: Positive . Power cord length: 50cm. Mount Hole for 7/8inch-11/4inch Handlebar. Package Included: 1 X Motorcycle Dual USB Charger LED Voltmeter Port