Compatible with all ZF 12-speed AMT gearboxes, made of high-quality alloy steel through precision forging and mirror polishing. It has ultra-high surface finish, moving smoothly back and forth without jamming. Resistant to high pressure, corrosion and fatigue deformation, it is not easy to wear and aging under long-term frequent operation. Manufactured strictly according to original standard size, it perfectly matches the oil seal structure with good anti-leakage and pressure maintaining effect, ensuring even pressure transmission and stable and sensitive operation of the brake assembly.