the dorade is th ebox on top of which the cowl vents sit. the dorade is designed to be a preventer for influx of wawr, and i have noticed mine work quite ell, as designed. if thwre is no box under the cowl vent,is not a dorade vent. is merely a cowl, and isnt gonna do what real dorade will do. if no box, you will want to cover your cowl or remove and place a deck
plate where the cowl vent screws into the deck
. should have come with the boat. if not-- there are sizes for these, 3 in and 4 in. if you prefer to become a carpenter
, the dorades are lovely and great for tripping over, as i usually do.... but they do keep out the more massive influxes of water
. look into wooden boat for instructions on how to make a PROPER dorade box for your cowl vents.