REPLACES ONAN NEEDLE AND SEAT KIT  142-0553.FITS MODEL 'DD' CARB ON ONAN TWINS WITH THE FUEL PUMP AS PART OF THE CARB .THESE ARE THE SAME N/S WE HAVE USED FOR YEARS IN OUR KITS.THESE ARE US THREADS A LOT ARE COMING  WITH METRIC THREADS THAT DO NOT FIT.