Scooter X-Max 125 52mm Cylinder Block Kit For Husqvama SMR SMS TE XRX 125 MBK Cityliner Skycruiser 125cc 4-Stroke This cylinder block kit is designed for use with specified 125cc 4-stroke scooter models.It includes a 52mm cylinder and piston assembly compatible with the X-Max 125 and other listed.The kit supports engine rebuilds or performance and is engineered to fit the specifications of the applicable models.Installation requires standard mechanical tools and knowledge.proper fitment with your existing engine components before assembly.