Lionel introduced the 153 Block signal in 1940. The signal features a green die-cast metal base, a sheet metal or later aluminum pole and a die-cast metal lamp head. The signal was sold until production stopped for the war in 1942. Then it was sold again after the war from 1945-59.
The earliest 153 Block signals had Aluminum painted sheet metal poles. In 1941 the pole color was changed to gray because the silver paint became expensive due to the war in Europe. After the war the aluminum painted poles returned. At some point in the mid-1950s the pole changed to unpainted aluminum.
The prewar version and postwar versions made before 1950 had screw in 6 volt bulbs. After 1950 12 volt bayonet bulbs were used.
The early signals with 6 volt lamps had resistors like the one shown on the right in the photo below.
The signal came packed in a box with a 153C contactor. Here’s instructions for wiring up the signal.
RARITY: None of the Lionel 153 block signals are rare or valuable. They are very common, and only signals that appear brand new with a complete and gorgeous box with inserts and packaging are desirable to collectors. They are nice for the layout.