Vent Works

If you’ve ever tried attaching duct to a square blower outlet, you know it’s not possible without an adapter. Most people don’t have the ability to make one and even if they do it usually takes way more time and effort than it should take.

This adapter gives you a clean, reliable square-to-round transition, and the 4” outlet is intentionally undersized just enough so any duct slides on easily… flex, semi-rigid, or solid. No forcing it. No wrestling with it. Just a smooth, tight, professional connection every time.

Made in the USA from heavy-gauge steel.

Built for techs, fabricators, shop owners, and DIYers who want installs that actually go right the first time.

If you need a fast, clean way to go from a square blower outlet to a standard 4” round duct, this is it.