The Automatic Refrigerated Milk Car No. 3662 was one of the premiere operating cars that was produced by Lionel beginning in 1955. Early cars would have bar-end Type 7 (1955), and Type 7a (1956-59) trucks with either magnetic or tabbed couplers. Later editions would have early AAR (1959-60), and late AAR (1964-66) trucks equipped with disc couplers. These changes in the trucks account for three of the four variations of this car. The other variation involves the color of the roof (B Variation) which was DULL BROWN in color.

The car came with seven non-magnetic milk cans that were loaded manually through a hatch in the roof and were unloaded with the use of a 6019 or UCS track section on to the platform.