Warm Tip: When you receive your product, you can scan the QR code on the product to download the corresponding APP. We are very grateful for your love and support for our products. Specifications: Application: 27.5 Inch Front Wheel APP interaction: YES Generations: iMotor 3.0 Voltage: 36V Maximum capacity: 7.2ah(270wh) Maximum speed: 40km/h Maximum output voltage: 800W Motor Power: 350W Break: V Break / Disc Break Model: 27.5" Battery Number: 30PCS USB Output: 5V 2A Battery development: YES Charging Port: DC2.1 Assistance mode: Pure electric cycling / Pure pedal assist Condition: this is returned by others. He said the battery doesn't work. We can send you a new battery for replacement. Package: 1* bicycle front wheel 1* mobile phone holder 1* modification package 1* charger 1* instruct.