Features: 1.Material:Made of made from high-quality, weather-resistant ABS materials and rubber. 2.It fits round seat post diameter with 25.4mm, 27.4mm, 28.6mm and 31.8mm, such as mountain bike, road bike, e-bikes, electric bicycle and scooter. 3.Bike rear reflector conntected the bike airtag holder via quarter-turn mount, it is easy to install and dismantle by turning. 4.This bike Airtag holder hides your Airtag inside a bike reflector. It's a perfect way to hide the AirTag securely and looks like a ordinary bike light, a part of the bike. 5.Multi-directional reflective design allows the product to have a wide-angle reflective making travel safer. .