Keep in mind that they did make TWO versions to this ONE clamp. There is the standard version that ONLY fits STANDARD bars and weighs 1.4 ounces and theres the oversized version that ONLY fits OVERSIZED bars and weighs also 1.4 ounces. Both include 2x 6mm bolts.
31.8mm is compatable with standard bars with a slit using IHC, ICS, MINI HIC or threaded compression.
34.9mm is compatable with oversized bars with a slit using HIC or IHC with OVERSIZED or ALUMINUM bars.