LSM Racing Products has developed the standard for changing valve springs with the innovative design of the On-Head Valve Spring Compressor. These Valve Spring Compressors are simply the best quality and easiest to use; making changing valve springs a fast safe and simple one-man job. All LSM On-Head Valve Spring Compressors have a tapered flange retainer housing that can fit springs as small as .800" and up to 1.600". They can easily and safely handle 1,000 lbs. of seat pressure with our screw down method. Plus, you won't need an extra set of hands so you don't lose your keepers. No need to take off the pedestals, the compressors bolt right to the stands.