The Wilwood 2.78-inch adapter rotor/hat register ring comes as a two-pack and provides a defined seating diameter for matching rotors to hats. These rings are used when a 2.78-inch register is specified, helping ensure rotors sit true on the hat interface and maintain proper alignment during installation. They function as dimensional adapters for specific register requirements.

Wilwood Adapter Rotor/Hat Register Ring 2.78in Dia. - 2 Pack