Item DescriptionAsymmetrical design with an offset slot specifically for carbon seatpostsFitment based upon seattube sizes: 31.6-31.9 for 27.2 posts; 34.9-35.2 for 31.6 posts; 35.5-35.8 for 32.4 posts. 21gItem Specificationsdiameter: 34.9-35.2mm (31.6mm)color: black: