New Kalloy Bicycle Alloy Seat Post Clamp Without Bolt Anodized Silver - Brand new never installed - Made of aluminum alloy - Diameter: 1-1/8"(28.6mm)/1-1/4"(31.8mm)/1-3/8"(34.9mm) - Weight: 25 g - Compatible with M6 hex bolt or quick release - Please note the number on the seat clamp does not represent the size - The number is for manufacturer use only - Feel free to contact us if you have any questions - Thanks for looking