Replaces Part Number # 5TG-14101-00-00. Outlet side Outer Diameter: 50mm ; Outlet side Inner Diameter: 40mm ; Intlet side Outer Diameter: 56mm ; Intlet side Inner Diameter: 44mm. Compatible with YAMAHA WR400F 1998-2000 WR426F 2001-2002 WR450F 2003-2011, YZ400F 1998-1999, YZ426F 2001-2002, YZ450F 2003-2009. Easy to install, it's better to be installed by professionals(NO instructions included).
