XH&reg; Durable 34.9mm Front Derailleur Braze-on Adapter Clamp for Bike MTB Durable Front Derailleur Forged Clamp 34.9mm High quality clamp, you can use a braze on front on any frame without a braze on mount. Wider band clamping spreads clamp area pressure on the seat tube. Sizes available: 34.9mm Material: Aluminum