Davis Instruments homepage features details on the Doel-Fin stabilizer.
According to Davis Instruments, the Doel-Fin stabilizer maximizes lift at any speed, while minimizing drag, it reduces planing times and fuel consumption by up to 30%.
The original hydrofoil on the market, the Doel-Fin uses a true foil shape unlike competitors. Employing two pieces of guaranteed-unbreakable, high-strength plastic, it creates better stability and control, even in rough waters. Each fin is designed to flex independently,absorbing shock.
Perfect for outboards and outdrives on all boats from small, inflatable dinghies to large ocean cruisers, the versatile Doel-Fin decreases stern suction and bow rise for better visibility and safety. With faster out-of-the-hole performance, it enables higher top-end speeds and steadier turns.
Source: Davis Manufacturing