There are six different instruction sheets that were printed under the No. 450-42. These changes resulted because of the addition of the inventory numbers of the replacement lamps, and because Lionel introduced new transformers during the period when this bridge was in production, and also because the address of their service department changed. The dates on these sheets are: 10-52, 4-53, 3-54, 4-55, 12-55, 2-57. All of these instruction sheets used DARK BLUE ink on WHITE paper. We’ve shown the front and the back pages from the March 1954 sheet below.

Dimensions: 7-1/2 inches high, inside height is 6 inches
Base: 3 inches long, 1-1/2 inches wide
Distance Between Bases: 7-1/2 inches

The Signal Bridge No. 450 spans two tracks and has two signal heads that have bayonet mounted lamps that change from GREEN (Lamp No. L53G) to RED (Lamp No. L53R) as a train approached.

This was accomplished with the use of the No. 153C Contact that was placed beneath the track and changed the color of the signal indicator because of the weight of the train. The No. 153C contact to the bridge was accomplished with three wires that are connected to the wire clips in the base. See the picture below. Extra signal heads could be purchased under the No. 450L.