.350" THICK X 12.19" O.D. SCALLOPED INBOARD ROTOR8 X 7.00" BOLT CIRCLE WITH DYNAMIC MOUNTINGDYNAMIC MOUNTING IS THE MOST EFFECTIVE METHOD OF ELIMINATING ALL TYPES OF THERMAL STRESS & DISTORTION IN STEEL ROTOR APPLICATIONSTHIS ROTOR IS MACHINED WITH MOUNTING SLOTS THAT ARE USED WITH SPECIAL "T-NUTS" & BOLT KITSTHIS MOUNTING SYSTEM ALLOWS THE ROTOR TO EXPAND & CONTRACT INDEPENDENTLY OF THE MOUNTING HAT OR HUB AS THE ROTOR GOES THROUGH TEMPERATURE CHANGESTHIS ELIMINATES ALL STRAIN OR BIND AT THE MOUNTING POINTSTHE ROTOR RUNS TRUER, LASTS LONGER, & ALL UNDO STRESS ON THE HATS OR HUBS IS ELIMINATEDDYNAMIC MOUNTING IS PREFERRED IN ALL APPLICATIONS WHERE TEMPORARY, BUT EXTREME TEMPERATURE SPIKES MAY CAUSE HIGH EXPANSION RATES IN THE STEELDRILLED & SCALLOPED DESIGN ELIMINATES ROTATING WEIGHTWEIGHS 4.8 LBS.BUILT FOR RACINGMADE FROM HIGH QUALITY, HIGH TEMPERATURE STEEL