ABN Overhead Valve Spring Compressor Keeper Seal Install Tool Overhead Valve Spring Compressor Keeper Seal Install Tool, Removes and installs valve springs, spring retainers. Simplifies work by eliminating removal of the cylinder head. Adjustable cam action creates a secure fit to the valve spring. Designed for a wide range of OHV, OHC and CHV engines. Do not need to readjust the tool after each spring, use with compressed air to hold up valves.