Description Strange Evolution Series Rear Brake Kit for ’57-’64 Olds Housing Ends Evolution S Rotors, Directional Slotted Rotors Uni-Lug Rotors Drilled 4-1/2″, 4-3/4″ & 5″ bolt circles for both 1/2″ & 5/8″ studs 4 Piston Billet Evolution Calipers Semi-Metallic Brake Pads Requires • Ball style axle bearings * • 2.832 in. brake offset (2.75″ common) * Caliper mount relief is not correct for tapered bearings