Treks Removable Integrated Battery System looks good and is user-friendly: it is completely integrated into the frame, providing excellent protection, can be easily removed without tools, and even leaves room for a bottle cage; This bike expands horizons: the top-notch Bosch system is equally suitable for daily commuting, recreational rides, and great times on the trail; 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.