The Bascule Bridge No. 313 was a carry over accessory from the pre-war era. Lionel would, however, make some changes in the way the bridge was raised and lowered. In the pre-war version the bridge would be raised by a series of gears attached to the motor. But in the post-war version the bridge would be raised by a spring drive and there would be changes to the bridge itself to accommodate this drive. Another way to tell the difference is by the bridge itself. Pre-war versions are painted GRAY or SILVER sheet-metal, while post-war versions are unpainted SILVER aluminum.

This bridge would stop the train automatically in insulated track sections placed on either side of it when the bridge was in the raised position.

Early versions of this bridge (Variation A) would have a plug-in lens cap (Part No. R-68) on top of the bridge that was identical to those used by the R, V, and Z transformers. Later editions of this bridge (Variation B) would have a ribbed screw in type lens cap (Part No. RW-27). These parts are not interchangeable. Produced from 1946 until 1949.

Dimensions: 21-1/2 inches long (level), 9-1/4 inches high.