Plentiful Power for the Performance Dollar Boasting the highest horsepower in its class, the Jet Ski® STX®-15F watercraft is a natural when thoughts turn to summer days and skipping along choppy ocean waves or cruising calm lake waters. With a hull that ensures stability on the straightaways and great cornering while turning, the STX-15F defines liquid fun. It’s packed with rider-friendly features, including class-leading storage that lets you take all your gear with you for a day of fun out on the water. And with 160 horsepower, the STX-15F has the most powerful engine in its class.