These gears are required for cam UPGRADES on the 2012+ models. If you have the 3bolt design these will convert you to our one bolt design. ALL OUR CAMS ARE SINGLE BOLT DESIGN.
It will convert you from 3-bolt style which are prone to slip when retightened, to the GEN1 style with the flat style holder and single bolt design.
SIMPLER, EASIER. AND PIECE OF MIND.