Note the narrow plastic strip on the trailing edge of the prop. These change the pitch. Each color strip is a different height, thus creating a different pitch.

Viking, Bertram, Cabo, Riviera and other major builders of high-speed convertibles are using Veem props because of the Interceptor technology you see pictured above. Several things can affect the performance of sportfishing boats as they try to maximize speed, including tuna towers, fuel loads and weight distribution. Changing prop pitch to maximize performance used to mean changing props – but not with Veem's Interceptor props. Now all builders have to do is change the plastic strips on the trailing edge of their props. Watch Capt. Smith explain the technology in this short video--

Visit Veem's website--