Developed on our Dyno and tested extensively on the water, this waterbox features radiused exhaust tubes and end caps for optimum exhaust flow. Unique exhaust baffle will increase the low-end power and mid-range pull of your Yamaha watercraft. Delivers up to 15hp on modified engines along with significant torque gains. High-strength aluminum construction will survive backfires and meltdowns. Powder coated to prevent corrosion. A must for modified motors.