New Proform valve spring remover/installer. This is for use on the vehicle. Simply fill your cylinder with air, install the mount block in place of 2 rocker arms, tighten down the nut, and it compresses both intake and exhaust springs at once. For LS1/LS2/LS6/LQ4/LQ9 cylinder heads. Does not work with LS3/L92 nor LS7 heads.
NOTE : Certain large diameter springs may require grinding the mount block for adequate clearance around the tool.