Description: Foldable Bicycle Extension Seat Bike Wheel Set Support Convert Seat. Fit for 20 inch frame 406 changed to 451 wheel set. This bicycle extension seat is made of qualified aluminum alloy, solid, firm and durable to use. It is possible to change the brake of the original V-brake position to the support position in the frame, so that the overall appearance of the car will look better. Integrated production, surface anodizing, corrosion resistance, higher hardness. Specification: Material: Aluminum Alloy Size: 35x22.2x24mm/1.38x0.87x0.95inch Package Includes: 1 Piece Extension Seat 1 Piece Screw Note: Color might be slightly different due to the color calibration of each individual monitor. Please allow slightly measuring deviation due to manual measurement.