Vmax+ 180 ALTO features Brake Sensing Technology, indicating to those following behind that you're slowing or coming to a stop. The Vmax+ 180 ALTO also features COB (Chip-on-Board) LEDs, which for cyclists means it emits highly visible flash patterns in a smaller, more compact package. Its feather-like light weight makes it perfect as a wearable safety light—easily clipping onto straps, belt loops, and more! For added convenience, the Vmax+ 180 features mode memory, will power ON in the last mode used. Features: Lumen Output: 180 7 Modes with Run Times: 4:30-24:00h Charge Time: 2:00h Weight: 59g Li-Po | 3.7 Volts | 524 mAh | 1.94 Wh Brake Sensing Technology Water / Dust Resistant IP64 Rated USB-C Rechargeable Mode Memory (Powers ON in last mode used) Fits post diameter sizes ranging from 15.8mm - 31.6mm. 27.2mm is the most common seat post size. Run times per mode: Fast Flash - 11:30h Slow Flash - 9:30h Disco Flash - 8:30h Econ Flash - 20:00h Pulse Flash - 5:45h High Steady - 4:30h Low Steady - 24:00h *Run times are approximations and may vary