Dryer Vent Installer Kit The great thing about this item is that its venting system allows the wall vent to protrude up to 2-1/2" without having to be trimmed. The kit includes an extension collar that allows it to have a universal 4-1/2" clearance. This installer kit does a wonderful job of utilizing loop systems and DuraSafeª patented snap-lock fittings. Packaging includes 4-foot vent section that attaches to a close elbow, one 4-foot vent section that attaches to a wall offset, and an extension collar. Total length of this item is eight feet. Keep in mind that additional vents can be snapped between sections for longer runs.