A front flange gable louver is the most common and easiest vent install. With a nail fin protruding from the face edge of 1 1/2", it is ready to cover up any rough framing boundary for the simplest sealing.
Install the louver vent first with the nail fin attached to the wall cladding. Apply siding, stucco or brick snuggly around the vent face. The flange on the rear of the vent frame acts as a water deterrent.
There are no strings attached to this one. Cut the opening 1/2" wider and taller than the ordered gable louver and slide the vent into the opening, then seal the face off. Goes great with brick openings, removed attic windows, and anywhere exterior trim may be applied after.