CNC machined from 6061 billet aluminum with the proper 1.59” offset for compatibility with our caliper and caliper mounting brackets. This hat can be used with a stock cast iron 1965-67 Mustang disc brake hub or our own billet disc brake hub for easy “slide-on/slide-off” rotor removal. Buy this hat once and then simply replace only the rotor when needed for cost reducing efficiency. Makes rotor replacement on the vehicle a snap. Designed with a common 8 on 7” rotor bolt pattern, this must be used with our racing rotor. Aluminum finish. (For standard Ford 5 on 4-1/2” wheel stud pattern.) 7.620" diameter.