QUALITY MATERIAL: High quality, CNC machined and hollowed lever, this quick release seat post clamp is extremely strong and lightweight. You can easily install it on your bike even if you are not a professional under repair. RUSTPROOF & HIGH PRECISION: High quality rust resistant lever and thumbscrew hollow design for precision and a quick release lever for ease of use. The surface after anodized grinding treatment, smooth and shiny without edges and corners. EASY TO INSTALL AND USE: Easy to install and use, the clamp diameter you need is the frame and NOT the seatpost diameter. It's ideal for all styles of bikes that need a seatpost. SAFE AND NON-SLIP: Designed to provide effective clamping action without slipping, even in wet and muddy conditions. WIDE APPLICATION: 34.9mm seatpost clamp is usually suitable for 30.8mm-31.6mm.