Harbour Tug Boat - Yellow. Additional portholes give this tug real character. £8.50 Out of stock Large Pop Pop Tug Boat - Yellow. Additional portholes add character to this model. After this boat has been running for a while, smoke will flow from the chimney. Steam Powered Length 6" (15.25cm) Includes Fuel Tray, Candles and Priming Dropper.