EBC GD434 86-89 Mazda RX7 2.4 (1.3 Rotary)(Vented Rear Rotors) GD Sport Rear RotorsEBC GD434 86 89 Mazda RX7 2. 4 (1. 3 Rotary)(Vented Rear Rotors) GD Sport Rear Rotors Product Information EBC Sport Rotors feature wide aperture slots that draw cool air into the braking contact area and reduce temperatures preventing brake fade. Dimple drilling avoids stress cracks and the anodized EBC finish provides a great look while preventing corrosion. EBC Sport Rotors now feature reduced 3 slots venting which provides slightly less air noise