Transition – Used to form a junction betweenWD06W350-FST 6" [152mm] 8" [203mm] flush and surface Wallduct at a 90° angle.WD10W350-FST 10" [254mm] 12" [304mm] Includes assembly screws, clips, one wireWD18W350-FST 18" [457mm] 20" [508mm] retainer and two coupling angles.