Weight: 30g Size: 34x30mm Included: Tail light body, instruction manual, rubber bands (large, small), seat post mount, gasket for mount installation, side rail mount, 4 cable ties, charging cable (Type-C) Waterproof: IPX6 Charging: 300mAh (15-80 hours) ・Brake warning function: Emits light at maximum brightness when braking or decelerating ・Light and vibration detection automatic on/off: Automatically turns on in dark places or with vibration, and automatically turns off after 30 seconds in bright places or after stopping ・Automatic/manual mode switching possible (switch by double-clicking) ・5 lighting modes: Red light flashing (25 hours), red and blue alternating flashing (30 hours), 7-color breathing flashing (20 hours), red light rapid flashing (80 hours), red light constant on (15 hours) ・USB rechargeable (300mAh built-in, USB-C charging, fully charged in about 2 hours) ・Charging status indicator: Easily check with 4 blue lamps ・High-strength aluminum alloy exterior: Lightweight and sturdy, excellent impact resistance, heat dissipation, and corrosion resistance ・IPX6 waterproof: Usable in bad weather and on bumpy roads ・Easy installation: Compatible with seat rails or seat posts, necessary tools included Discounts available for bulk purchases. Please take a look if you'd like.