The Saf-T-Duct Dryer Outlet Box from Builder's Best finishes off dryer vent rough-ins and easily adds or recaptures space in the wall behind your dryer for venting. The unit can be used in-wall (prior to drywall) or on-wall (after drywall is installed). The standard 4 in. round connections allow for the best airflow and connect easier than ovals. | Builder's Best | | Saf-T-Duct Dryer Outlet Box | White | Best Buy