These Magnetic Vent Covers are used in conjunction with metal floor or ceiling air register vents and help to improve air distribution in the home by closing off registers in unused spaces. This 8 in. x 15 in. version is plain white and can be cut to size to accommodate a variety of various registers. 3 vents per 1 pack.Improve air distribution by closing off registers in unused spacesCan be cut to sizeSaves energyCompatible with all metal registers