While I can't personally confirm it will work on a Regal, a couple of Amazon reviews state it will work on multiple w-body models. Take that for what it's worth.
Awesome! If you have a GM W-Body car (Chevy Impala, Pontiac Grand Prix, Buick Regal, Olds Intrigue, etc.) This is just the thing to keep rain water from soaking your cabin air filter before ending up in your heater box and all over the floor. Simple installation and fixes a bad design!This worked great on a 1999 Buick Regal LS. I had to modify my vent cover slightly by cutting plastic off of it so that it wouldn't press up against the new deflector cover, which was easily done by using a small saw to cut it away so that it would fit.