High-performance air shock absorber: The suspension provides smoother driving and better overall damping management, improving driving comfort, motorcycle handling and driving safety. Copper sleeve size: upper 12mm, lower fork: 25mm wide, M10 screws Compatible with CB400SF (NC31/NC39/NC42), CB400SS/CL400, etc. XJR400 (4HM/RH02J), SR400/SR500, etc. GSX400 Impulse (GK79A/GK7CA), Lightning 400, etc. Zephyr400 (body number: ZR400C).Most 50cc, 75cc, 90cc, 125cc, 150cc, 250cc, 300cc street cars, off-road vehicles, karts, ATVs, motorcycles and quad bikes Oil seal by N.O.K (japanese high standard). The eye of shock has tensile strength moree than 2000kgf. The dumper and spring designed for long durability(more than 1 million). Max loading:180kg/piece 400lb/piece. Our products are made by high-qualified materials with japaneses technology and the advanced computer numerical control processing. the quality is strictly monitored by ISO9000 standard to make sure the excellent performance and the g