Fill through filler neck and Cap
From Tanks, Inc.
This spout assembly in comprised of a tube and collar that screw together to create a 2" o.d. and 3-3/4" long spout.
The unique Tanks FILL THROUGH gas cap design means YOU NEVER HAVE TO REMOVE THE CAP! The gas pump nozzle slips through the flap valve in the center of the cap. It couldn't be easier.