This TIF KT3303 PROMAX Valve Replacement Kit is to be used on the old style (round cylinder) and new style (rectangle Cylinder) compressors on RG5410 series, MiniMax Series and PROVAC Compressors. Kit includes all necessary parts to rebuild damaged seals and valve assembly. Use caution not to disturb the lower end when disassembling the upper end or their seals will need replacement as well.