Tin Toy "Robin Boat" Classic Pop Pop / Steam Jet Boat / Candle Boat with Recoil Drive. "The Knatter-, Putt-Putt- or Puff-Paff-Boat is a toy boat with water impulse drive (steam jet drive, pulse motor, pulsed waterjet). The simple engine operates without moving parts such as pistons, valves, or wheels. A candle or another heat source serves as the energy source. At the stern of the boat, two pipes protrude side by side and parallel below the waterline. Water is drawn in and expelled through the pipes. The characteristic rattling noise that gives the boat its name is not directly caused by the evaporation process, but by a special construction of the evaporator: The top is shaped from spring steel sheet as a clicker frog, which jumps back and forth during the rapid pressure changes, producing a clicking sound each time." (Source: Wikipedia) Material: Tin Size: approx. 14 x 7 x 3 cm (L x W x H)