Name:Quick Release Clamp(31.8MM) Material: 6061 aluminum 31.8MM (for seat post diameter: 27.2MM, 28.6MM) Size(31.8mm):6.5x6x1.3cm 31.8mm weight:36g Anodized surface treatment process, quick release locking design High-strength lightweight design, 6065 aviation aluminum alloy, T6 heat treatment, lightweight design, fine workmanship. Simple removable assembly design, high strength nylon gasket, not brittle, wear-resistant and pressure-resistant, not scratching metal parts. Fine cutting treatment, corrosion resistance, surface frosting process, strong texture, bright color.