Based on the “nodding donkey” style pump working oil fields across the country, this new accessory features the smooth bobbing action of the real thing. Add two or three oil pumps to model this common industrial scene. Plug-N-Play Accessory: Connects easily to FasTrack with a Plug-n-Play Lock-on (sold separately), Connects to a traditional O/ O27 track lock-on or to an accessory power supply (lock-on and power supply sold separately), Can be upgraded to command control with the purchase of a SC-2 Switch Controller or an ASC2 (both sold separately).