New Vernalift Wet Marine Exhaust Muffler centek 1500027 Ports 2" Height 10-5/32" Base 10-1/2" : Extremely effective in reducing engine exhaust noise and preventing water from returning to the engine. High strength design provides a significant safety margin over other existing fiberglass lift mufflers. Exceeds ABYC specifications. For use above or below the waterline.