Featuring a profile machined face, this clamp is structurally balanced putting the material and strength where needed. The Arc SCS uses the same custom bolts as the Classic SCS with a 6mm hex key drive and 50% larger threads provide more clamping power and help keep the compression tight and bars in place. Every clamp bolt from Tilt comes with pre-applied anti-seize to prevent them from seizing to the clamp. For added compatibility, the removable shim allows use with both Standard and Oversized bars WITHOUT A SLIT. All new production of TiLT SCS Clamps will come with the new M8 compression bolt and matching Compression washer. There may still some back stock of the old M6 bolt and washer. If you need one over the other please specify in the order comments and if possible, we will supply you with the correct compression bolt you need. Compatable with Oversized and Standard Size bars. Shim Included