Exhaust system with function, because the integrated LED and the generated steam make it look as if the system is actually in operation and the engine is running. The red LED makes the exhaust appear glowing and the fog acts as if real exhaust gases were being emitted. The control box is connected to the receiver and the more gas you give on the remote control, the more steam comes out of the system. The ideal addition to get even more realism and attention to detail.