Now that SRAM's flat mount caliper design is becoming the brand's standard, you'll want to have the SRAM Flat Mount Caliper Bracket in the garage to mount the calipers onto your road disc frame. Up front, you'll need the adaptor whether you're running 140mm or 160mm rotors, as well as if you use a 160mm rear rotor. If a 140mm rear rotor suits you just fine, you'll be good to go without the bracket.