Yes, you can use Vanity Vents right on top of your unsightly Styrofoam vent covers, no problems!
About Vanity Vents
Vanity Vents will help to weatherize your home foundation crawl space and increase the value of your home with greater curb appeal. Homes with the best curb appeal sell faster and for more money on average. If you are tired of dealing with Home Depot Styrofoam crawl space vent covers and want an alternative to Lowe's Styrofoam vent covers then Vanity Vents are for you.
Open outside crawl space vents are not energy efficient. Open exterior foundation crawl space vents let cold air fill your entire crawl space under your home in the Winter months. And it works the same on a hot 80-degree Summer day. If it is 30 degrees outside, then your home is sitting on top of an ice cube. Or on a heating pad on an 80-degree day. You can reduce your utility heating and air-conditioning bills. Vanity vents installation takes literally 3 seconds.