OC – Oval Concave (60×140 mm/2.5×5.4″)Read more OC – Oval Concave DURAFLEX® (35×90 mm/1.4×3.7″)Read more OCF – Oval Concave Friction DURAFLEX® (20×80–40×110 mm/0.9×3.3″-1.6×4.5″)Read more