LGB 23193-066 Mogul Chassis/Gearbox Center (w/ out Top & Bottom Lids)

This is the newer style gearbox, designed for a 4 pin gearbox, which may be used to replace the older 3 pin configuration. 

LGB 23193-066 Mogul Chassis/Gearbox without Top and Bottom Lids

The top and bottom are sold separately and can be found under 20280-M017