KCNC SC13 Twin Seatpost Clamp 34.9-31.6mm Alloy BIKE - RED Model: SC13 Size: Seat Tube: 34.9mm / Seat Post: 31.6mm Color: RED Material: 7075-T6 Alloy WEIGHT: 28g Twin titanium bolts ( gold nut bars )  Concealed inner o-ring design, ideal for carbon seatpost to avoid slippery falling  1 pc/pack"