Sixteen Class 121 single-car, double-ended driving motor vehicles were built from 1960, numbered 55020-55035. These were supplemented by ten single-ended trailer vehicles, numbered 56280-56289 (later renumbered 54280-54289). They have a top speed of 70 mph, with slam-doors, and vacuum brakes. The driving motor vehicles were nicknamed Bubble cars . The Dapol Model of the Class 121 and 122.

Features:
– Finely moulded body with many separately added fine details
– Accurately applied livery
– DCC ready
– DCC fitted models available
– Cast wheels with fine relief and appropriate colouring
– Tungsten chassis and all wheel pick up
– NEM pockets as standard
– Independently controllable and switchable directional lighting
– Dapo s 5 pole skew wound mega creep motor for smooth running and fine speed control
– Accessory bag with spares and other optional detail