Exhaust oxygen sensor has 18mm X 1.5mm threads. Sensor is for the front or rear cylinder. FITS HARLEY: 2007-2012 FXD, Front or Rear Exhaust Sensor 2007-2011 FXST, Front or Rear Exhaust Sensor 2009-2009 FLT, Front or Rear Exhaust Sensor 2007-2011 FLST, Front or Rear Exhaust Sensor
