The Treks Removable Integrated Battery System looks good and is user-friendly: it is completely integrated into the frame providing excellent protection, it can be easily removed without tools and even leaves space 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 comes with 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 on or off the bike.