Weight: Measured 23g Mirror Shape: Convex, Φ30mm Compatible Inner Diameter: Φ16-22mm Manufacturer: WESTBIKING (China) Included: Hex wrench This is a rearview mirror that replaces the bar end caps of a bicycle. The mirror is foldable and matches the appearance of road bikes, etc. The hinge is ball-shaped, allowing for adjustment in any direction. Also, the fixing bolt allows for rotational adjustment around the central axis. It can be used with drop handlebars, bar handlebars, etc. The mirror is made of acrylic, which is less likely to break than glass. The inner collar expands and secures when the cap bolt is tightened. Caution is required for carbon handlebars, etc. Shipped via anonymous delivery. If you purchase this item with other bicycle accessories, we will discount the shipping cost for items that can be shipped together.