31.5x40x4 Motorcycle Pipe Gasket For Honda CB250 ATC200X ATC125M XL350R XR600R NX650 31.5x40x4 dimension port Fit For Honda motorcycle ATV models for header pipe sealing assembly Standard size design allows direct bolt on replacement without grinding or reshaping during system temperature composite material continuous anti vibration thermal deformation for off road street riding Creates complete airtight seal to leakage reduce abnormal popping noise keep stable engine backpressure Single piece flange gasket for individual vehicle repair daily commuting trail riding ATV projects