This air cylinder block is compatible with CRF150R motorcycles from 2007 to 2023.It is designed as a replacement for part numbers 12100-KSE-670, 12100-KSE-671, and 12100-KSE-672.Constructed from aluminum and ceramic materials, it features a 66 mm bore diameter.Dimensions are 77 mm x 72 mm x 66 mm x 59 mm and 51 mm x 29 mm.The unit weighs 631 grams and has a silver finish.This component is intended for off-road engine applications and is tested for proper fitment and function on the specified model.