The Lionel SP Caboose No. 4357 was issued in 1948 and 1949 as part of the "Electronic Set." Each of the cars in this set, including this one, had a radio frequency receiver on them that would allow them to be uncoupled anywhere WITHOUT the use of a UCS track section. The color of the decals on these cars determined which button to push on the ECU-1 Transmitter to uncouple the car. This caboose had a DARK BLUE decal with a Lionel "L" that read "ELECTRONIC CONTROL" and was located between windows 3 and 4.

Produced on Die 1, 2, or early Die 3 on a TUSCAN body with staple-end trucks and electronic coil couplers. The B Variation does not have the extra catwalk board, See Die Type Details.