Fuel Tank Sender: 61-64 - 3/8" Chev / Ponti Big CarThis brand new reproduction sender unit comes with the seal and locking ring as well. Suitable for the 61 64 3 8" line size Full Size Not for vehicles with a return line which is 99% .. don't' have return lines in this model year.. and NOT for wagons. A return line is easily seen as 2 pipes coming up to the bottom of the fuel pump from the fuel tank.. one line bigger then the other. Suitable for the 61 64 5 16" line size also as is a slightly larger