White boat vent cover holds 4" blower hose on a 1.5" smooth barb that allows double clamping if desired. Enough grill to keep trash and critters out, but still allow maximum ventilation.
Dimensions: The flange is 4-7/8" in diameter overall and installs in a 4" hole with 2 screws (not included).
If your vent grill looks like this and is this size, this is your vent!