For years, in the winter, I have been fighting with the drafts coming from my AC vents. Annually I would remove the vent covers and stuff Styrofoam in the vent to cut down on the drafts. After ordering and installing the 11×11 covers I can actually sit under the vents and not feel a draft. The units seem to blend into the ceiling and they are not an eye-sore. The staff was extremely accommodating in helping me install some vents over smaller openings and they function as advertised, also. We are very satisfied with these vent covers.