This is a Train Control Systems 2000 KA3 Keep Alive. The Keep-Alive™ (KA) devices are used to supply power to decoders during times of power interruption due to dirty track or problematic track work. KA3 will power an HO-Scale locomotive with headlights on for approximately 6 to 20 seconds (depending on the locomotive and the efficiency of the motor). This Keep-Alive™ includes a blue and a black w/ white stripe wire with which to attach it to a decoder. Dimensions: 1.02” x .45” x .347” or 25.9mm x 11.43mm x 8.81mm.Condition: Factory New (C-9)Operational Status: FunctionalOriginal Box: Yes (P-9)Manufacturer: Train Control SystemsModel Number: 2000Scale/Era: HO ScaleModel Type: ControlThe Trainz SKU for this item is P12197051. Trainz Product Id: 12197051