Fun Expression ChangeThis intelligent sensing facial expression taillight ensures riding safety while providing a variety of facial expression types, with up to 13 options that can be switched freely. It subverts the single display effect of traditional taillights, adds interest to the originally boring bicycle accessories, and meets the current riding needs of cyclists. It is recommended to freely change according to the riding scene or the needs of the team. USB TYPE-C ChargingThe Tail Light is built in 5000 mAh rechargeable lithium batteryThese Taillights Are Equipped With the Latest USB Type-C Charging Technology.It comes with a charging cable, mobile power/phone charger can be charged at any time.The runtime varies from 4.5 to 22.5 hoursdepending on the pattern and with the power display function, low battery charging indication, timely charging more secure. Super BrightThis taillight uses 1414-77pcs lamp beads to be brighter and more powerful, emitting a powerful 100 lumen, 180 wide-angle red beam to illuminate your road, allowing you to be clearly visible day and night. IPX4 WaterproofThe fully upgraded IPX4 waterproof bike light allows you to ride in bad weather. Enjoy riding even in fog or rain! It's built with a high-quality shell designed for tough handling and knocking, with excellent impact resistance and heat dissipation. Easy to Install and AirTag InstallationSeat Mount: Comes with a hex screw; seat tube mount: Elastic rubber ring designed with four openings to fit snugly around most sizes of handlebars and seatposts. The taillight is detachable for daily charging and removal.