Polygon Carbon StemAn ideal upgrade to any modern road bike, the Polygon Carbon stem will enhance the looks and performance of your bike, whilst keeping the overall weight down too. If you want to achieve more precise handling and better power transfer without adding excess weight to your road machine, this lightweight road bike carbon stem is a perfect choice.Features: Material: Carbon Fibre Handlebar Clamp Size: 31.8mm Steerer Tube Clamp Size: 1.1/8" (28.6mm) Use: Road All clamping bolts included Buy Polygon Components from Chain Reaction Cycles, the World's Largest Online Bike Store.