... have an excellent wear resistance, high reliability and easy to mount and dismount, repair quickly on-spot.material: alloy steeltechnology: forging ... :16/70-20, 17.5-25, 20.5-25, 23.5-25, 26.5-25, 26.5-29, 29.5-25, 29.5-29, 29.5-35, 33.5-33, 33.5-39, 33.25 ... -35, 37.5-33, 37.25 ...