Used by team Honda Pro racers; This stabilizer is extremely adjustable and rugged. The unit comes with all hardware needed for an easy installation and mounts up to your 400EX in approximately 15 minutes; no drilling, welding, or grinding needed. The new Precision ELITE Model has a built in reservoir, wider and more linear adjustment range, and larger wear surfaces for even greater product longevity. Plus up to 65% better impact damping than previous models. The stock steering stem diameter for the 400EX is 1.125 dia. All known aftermarket stems will fit.