The Bar End Mirror is made of durable resin and is compatible with any ATB, hybrid, or commuter handlebar, whether Cr-Mo or aluminum. It includes two inner adaptors to fit wider-diameter handlebars, offering versatile installation. The mirror is foldable, providing added protection when not in use, making it ideal for on-the-go cyclists. With a compact design and lightweight construction, it's a convenient and practical addition for enhanced visibility and safety.