Thank you very much for viewing this product. Aluminum 20CM Black Material: Aluminum, Rubber [Increase Mounting Locations] This is a bicycle extender that allows you to add more accessories like flashlights and cycle computers. [Lightweight & Durable] Made of durable aluminum alloy material, it is strong and long-lasting. [Includes Installation Tools] Includes hex wrench, screws, and non-slip rubber. Installation is complete by tightening the screws. [Applicable Range] Fits bicycle handlebars and adds extra storage space for bicycle lights, speedometers, GPS devices, phones, etc. [Specifications] Compatible handlebar diameter: 25-32mm (suitable for 31.8mm or 25.4mm handlebars) Note: For long-term use, the weight capacity is 1000g. Ships within 24 hours.