This grommet is necessary to install gas tank number D7DZ-9002C in a 1971–75 Maverick, because the emission hole in the original tank was larger than the hole in the D7DZ-9002C tank. Also, if you are installing D7DZ-9002C in a 1976–77 Maverick, you may want to purchase this grommet, because the old grommet is very difficult to remove from the old tank without damaging it.
For fuel vapor valve, see part number E7DZ-9B593VG.