Fit and compatibility: rearview mirror designed for handlebars with a diameter of about 15 35 mm (0.59 1.38 inches). Broad compatibility: suitable for various bicycles including city bikes, mountain bikes, road bikes, and electric bikes. Easy installation: self fixed, simple reflector can be directly installed on most handlebars without additional accessories. Wide field of view: flexible design provides a broad view of everything behind you, enhancing awareness during daily commuting. Key benefits Improves rear visibility and rider safety by allowing you to glance behind without turning your head. Quick, tool setup with no extra parts required; install and ride. Versatile across common bike types and handlebar sizes for convenient use. Use scenarios Daily urban commuting: navigate busy city streets with better awareness of vehicles and cyclists behind you. Recreational rides on mixed terrains: mount on road, mountain, or city bikes to monitor traffic behind during descents or crowd lines. Night rides or group rides: maintain situational awareness behind you on higher speed or social rides, improving safety in low visibility conditions.