Designed exclusively for Onemile Nomad E-bike; This battery functions as a removable detachable modular extended battery specifically designed for use with the Battery Extender Rear Rack Kit. It must be utilized in conjunction with a dedicated Battery Extender Rear Rack; The Rear Rack Battery Kit designed exclusively for Onemile Nomad E-bike, allows you to install a second battery to your Nomad e-bike. This offers an additional 100km range. Detachable Modular Extended Battery Includes: - 36V 10Ah Rack Battery Specification: -Charging time: 4 Hrs -Colour : Black