about this project 120 Lumens High Brightness & 5 Lighting Modes- 120 lumens high brightness bicycle tail light can better ensure your night riding safety, the discovery distance can reach up to 1000 meters, with 5 adjustable light modes to meet your various needs Various riding needs (modes: High 80lm, Medium 40lm, Slow Flash 80lm, Rhythm Flash 80lm, ECO Flash 20lm) Brake Highlight Warning Function- With built-in speed sensor, our bicycle backlight can sense braking deceleration, and will automatically increase the brightness to a maximum of 120 lumens for 3 seconds to warn pedestrians and cars behind, almost no signal from the bicycle False warnings about vibrations and jolts. Smart Mode Turns On or Off Automatically- Our smart bike tail light has a normal mode and a smart mode. In smart mode, it will automatically light up when you start riding, and it will automatically turn off after 45 seconds of riding, no need to operate the switch frequently, it is more convenient to use, and solves the trouble of riding. Forget to switch lights One-Piece Aluminum Light Body and IP66 Waterproof and Dustproof- The bicycle tail light is made of high-quality aviation-grade aluminum, with one-piece molding process and anodized treatment, which has better impact resistance, corrosion resistance and air tightness, which can reach IP66 Waterproof and dustproof, it can easily cope with various severe weather and environments, such as heavy rain, heavy snow, sandy or muddy roads, etc. Super Long 25 Hours Running Time, USB Rechargeable- The bike tail light has a built-in high capacity 500mAh rechargeable battery, which can be connected to any USB device (such as a USB power adapter or power bank) with the included USB cable for charging, etc. The maximum running time of the tail light can reach 25 hours (running time: High 2.5h, Medium 6h, Slow Flash 5.5h, Rhythm Flash 5.5h, ECO Flash 25h) Easy to Install, Multipurpose- You just need to attach the silicone strap with S-shaped hook to the seat tube to complete the installation of the Semaho bicycle tail light. The elastic silicone strap can make it more stable fixed on the bike.