The Sealey VS1601 Compressed Air Adaptor is a specialist valve spring compression tool designed for automotive valve train service and repair work. This essential adaptor works in conjunction with Sealey valve spring compressors (Models VS160 or VS168) to hold engine valves closed whilst the spring is compressed, making cylinder head work safer and more efficient. The adaptor features a spark plug adaptor design with both M14 and M18 threaded fittings, providing compatibility with the majority of car and light commercial vehicle applications. The integrated valve assembly is designed to maintain cylinder pressure even when the air supply is cut, adding an important safety feature during valve train maintenance procedures. Operating from a standard workshop air supply of 90-125psi, this compressed air adaptor provides reliable performance for professional technicians and serious automotive enthusiasts. Please note that a standard bayonet air line coupling is required but not included wi