COMP Cams Tools 5601 COMP Cams Valve Spring Compressor has a proprietary design that provides ultra rigidity in a lightweight package. This heads off spring compressor features a dual adjustable design that allows for perfect positioning and easy access to valves and springs. The spring cage has a small 1" diameter flange that works perfectly with most popular valve springs. Heads-Off Valve Spring Compressor COMP Cams Valve Spring Compressor COMP Cams ToolValve Spring Compressor