This corner air vent deflector is specially-designed to divert hot or cold blowing air from ceiling HVAC air conditioning registers away from the areas you want to protect. It is easy to install and fits standard-sized 2'x2' HVAC diffusers, vents, and registers. This air vent diverter redirects airflow without inhibiting or restricting the flow of air from your ceiling HVAC diffusers. As such, they should never be used in pairs to block an entire diffuser. This air vent deflector is made of durable 0.090 gauge polystyrene so it is built to last. It is white in color so it will blend seamlessly with most ceilings and HVAC air diffusers.