Treks Removable Integrated Battery-System looks good and is user-friendly: It is completely integrated into the frame, providing excellent protection, and can be easily removed without tools, leaving space for a bottle cage; This bike expands horizons: The top-notch Bosch system is suitable for daily commuting, leisurely rides, and a great time on the trails; The Purion controller features a Walk Assist function and an intelligent eMTB mode that automatically delivers the required power depending on the terrain; Thanks to the external charging port, you can easily and conveniently charge the battery in the frame or when removed.