Name:Rechargeable smartphone holder on Bike Item #:  GP1 Material:ABS+Silicone         Dimension:73mm*135mm*102mm Pipe Diameter: 20-35mm Battery Capacity: 5000mah Battery: Samsung 18650 battery cell Input: DC5V-2A Output: DC5V-2A Applicable size: 3.5-5.5 inches Smartphone Rotation: 180 degrees rotating at the perfect angle Waterproof: Water resistant / Rainproof Color: Black   product feature: Attention ! The battery of a mobile phone can only be used for half a day when using navigation. So battery power becomes the necessity of outdoor sports. GP1 smart power phone holder was made for the open road and was built for the ride. It features smartphone bike mount + 5000mah power bank 2 in 1 design, it can solve threes issues in riding: 1)Electronic devices such as mobile phones run out of battery easily in outdoor cycling 2)how bad to ride by carrying a bracket, power bank and other heavy equipment 3)It's inconvenient to keep navigation /calling /music control without a rechargeable hand-free bike mount.