Built with grade-A Samsung 21700 cells for 925 Wh of real-world energy—enough for up to 80 km of assist. A smart 6-layer BMS guards against over-charge, over-discharge, and thermal spikes, while the IPX6-rated alloy shell locks securely into any URBN X downtube mount. Weighs just 3.4 kg and ships with a silent 4 A fast charger (0–80 % in 2 h).