This 2 1/8" diameter shift ball fits on the OEM shifter and retains the OEM mount and boot lip. As many know the OEM shifter has a unique mount (no threads a slot on top and a screw to secure it). Universal knobs just don’t work here. Built using a custom billet insert and a 6spd ball you get a knob that fits the same as OEM, but is what many have been asking for.