Smart Home bicycle back light has smart sensor chip, the rear light will be turned to highlighted for 3 seconds, warning the rear driver to improve your safety when you have emergency situationThere are 6 light modes for you to choose from: Steady Light-12HBreathing Flash-16H Slow Flash-24H Rhythm Flash-24H ECO Flash-60H Fast Flash-23H. Different tail light modes provide more reliable safety escort. Make your ride more visible and clear, enjoy your ride to the fullest.USB rechargeable with a built-in 400 mAh battery that lasts up to 60 hours when fully charged. And 3 colors shows different situationGreen means in a healthy power levelBlue means the power level is between 30%-80%Red means you need to charge the bike tail light.LA Smart Home bicycle Rear light has IP66 waterproof and can withstand all types of weather conditions. Also it can be a helmet light, walking pet caring light and moreOur Bike tail lights fit any size bike seat cushion or bicycle seat tube.We provide a saddle mount bracket and an adjustable silicone strap that can be mounted on the saddle rail or seat tube,without extra tools, unscrew from the mounting bracket easily for charging.