This vent cover is designed to fit in any standard 16 by 8 inch opening. The vent cover mounts from the outside and tightens in place with four screws. This vent cover is open to allow air flow to come through. If an open vent cover is needed, these will match the vent covers used in our 145 CFM Double Fan with Vent Cover. It is also the same vent cover as used in our Grilled Solid Vent Cover.