RUSSELL Brk Dsc 79-91Xl 82-91 Fxr Available in standard design that deliver optimum braking efficiency with maximum heat dissipation Manufactured from SVS420JZ, a highly rust-resistant stainless steel material compatible with all types of disc brake pads (including sintered pads) High-frequency induction hardening, O.D. trueing and tempering prior to final surface grinding Computer-controlled process guarantees quality control and precise dimensions Replaces H-D #41791-79A Diameter: 11.5in. Hub Diameter: 2in.