A valve spring compressor is a tool for those who are disassembling a cylinder head and wish to remove the valves and springs within the head. One side of a valve spring compressor will brace against the valve on the base of the head while the other can be clamped down on the valve spring retainer. This action forces the valve keepers loose from the retainer which is what keeps the valve attached to the spring. A valve spring compressor can be used to both remove and install valve springs into a cylinder head. The Valve Spring Compressor is suitable for just about all small and medium Over Head Valve engines. The opening adjustability of this compressor is between 75mm and 165mm giving enough room for just about any head type. The throat clearance on this compressor is 150mm which allows enough clearance for the arm of the compressor to wrap around the side of the head. This tool is perfect for anyone that wishes to easily and quickly remove valves from the cylinder head. For any DIY mechanic who finds themselves regularly pulling motors apart, this is a must have tool.