Some boats used a similar but slightly different design from a different manufacturer who has gone out of business. It is no longer available. In the earlier design the hose clamped around the outside of the vent collar. That means that the inside diameter of the collar was less than the legally required 3" ID minimum.

This new vent will work in place of the old version. In this case the 3" ID hose fastens inside of the collar so the smallest inside diameter meets the required 3" minimum.

As a result, the mounting hole in the boat is slightly larger. You will have to enlarge the hole slightly to accept the replacement vent.

• Fore and aft (at base): 5-3/4"
• Width forward (closed end, at base): 3-5/8"
• Width aft (open end, at base): 4-3/8"
• Height: 2-1/2"
• Outside diameter of flange through the deck: 3.4"
• For use with vent hose diameter: 3"