Ancheer Bike Cargo Racks Cycle Bicycle Commuter Rear Carrier Rack Black ( US STOCK ) Ideally used with panniers, backpacks, baskets, etc. Frame-mounted for heavier top Fits 97 percent of all mountain and hybrid/road bike frames,durable, lightweight aluminum 712g Material: Aluminum Alloy, Rack Size: L33.0 x W11.5cm/ 12.87 x 4.49 inch, Fit Seat Post Diameter: 2.6-3.0cm/ 1.01-1.17 inch One year limited warranty