In addition, the propeller is specially designed for the SparQ. This is protected by a tunnel which increases the efficiency and makes the boat very manoeuvrable. In this way, we get the most out of the batteries and ensure smooth sailing. In addition, the propeller is specially designed for the SparQ. This is protected by a tunnel which increases the efficiency and makes the boat very manoeuvrable. In this way, we get the most out of the batteries and ensure smooth sailing.