The Assault RC Perfect Damper Rebound Gauge is the PERFECT tool for racers who are meticulous about their setup and dampening.  This tool is meant to help racers set rebound in their shocks perfect every time on every corner.  With 1mm increments starting at 1mm and going all the way to 8mm you now have a tuning option that didn't once exist.  Great for all genres of racing from On-road/touring, Oval, Off Road and even crawling.  The tool fits perfectly into your plano tool box or in just about any drawer imaginable.  It's better to have than have not.