Rubber stoppers on my excursion were trash so i designed this "plug" looking thing to get the stance of the fuel door correct again. Printed in TPU with few walls and low infil time will tell but pops into place and  holding up well now for little while. my plug holes were 4mm so that is what i modeled it after i cant imagine every vehicle having different bumpers for  their fuel door so guessing this could work for many vehicles but unknown as i only needed to fix this vehicle. Let me know  what else it could fit or  if there is other common sizes i can add to this.