Overview: Installs on standard tyre air stem valve of cars, motorcycles or bicycles. Durable, high impact, water & rust resistant. Chrome body with Ultra bright, long life span LED lamp. Automatic sensor turns on when wheel is in motion. Increases nighttime driving safety. Operates on 3 pieces of button cell batteries (included) Specification: Weight Approx:25.2g Size Approx:3.8 x 1.7 x 1.7