Builder's Best SilverDuct (TM) UL listed Dryer Transition Duct attaches BetterVent Indoor Dryer Vent to the electric dryer exhaust port. Measures 4" X 8'. Includes 2 reusable plastic clamps. When combined with the Builders Best Close Elbow your dryer can be place as close as 4.5" from the wall. Made in USA.