Aluminum alloy bicycle horizontal extension frame. Compatible with 31.8mm and 25.4mm handlebars. I installed it once to attach a drink holder, but it became unnecessary, so I removed it without riding. It can be used without any problems, but there are minor scratches from the installation. Please understand this before purchasing. Bicycle Handlebar Extension Bracket Aluminum Alloy Bicycle Holder Lightweight Extension Mount Accessory Holder Easy to Install Fits Standard 25.4mm and 31.8mm (Black) - Type: Horizontal extension frame - Material: Aluminum alloy - Length: 20.2cm - Compatible size: 31.8mm and 25.4mm handlebars Thank you for viewing.