compatible with vehicle, its better to choose power positive pole from ACC than BATT+; compatible with motorcycle, its better to get power from key switch.The digital LED only shows up when the item is connected to the power and the switch is on.Since the iPhone series does not support fast charging, so their charging speed is normal.LED Voltage display]can monitor car battery voltage status in real time to prevent personal safety and property damage from battery failure.Dual Quick charge 3.0 USB Port Simultaneous high speed charging compatible with two compatible devicesThe use of on-off switch compatible with power control design can prevent power failure, save energy and extend the service life of the product.Specifications:USB output voltage: less than equal 12V.Output current: less than equal 6A.Maximum power: 36W.Output of each USB port: DC 3.6-6.5V / 3A, 6.5V 9V / 2A, 9V 12V / 1.5APower supply input: DC 12V-24VInput current: less than equal 10AMaterial: Aluminum alloy+ABScolour:Black blue lightPackage Contents:1 x USB socket charger2 x Insulated Terminals1 x HarnessOnly the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.