This V-shaped Kerf Weatherstrip is a hassle-free way to insulate your kerf door frames and prevent infiltration of sound, water, and drafts through the door cracks, making your home more energy efficient. Its convenient design does not require adhesives, making it easier to remove and install than other forms of weatherstripping. Material: Foam kerf-in weatherstrip is constructed from soft cell foam enclosed by an embossed, tear-resistant, low-friction, UV-stable polyethylene cover. Shape and materials conform well to irregularities in door fit and finish for a tight seal and low air infiltration. Installation: To install, simply insert the extending flange into a kerf, or groove, and push in with the aid of a putty knife to get a tight fit. Compliance: The foam seal is fire-rated. Minimum Space Required 5/16"; Maximum Allowed 1/2"; Width 5/8"; Kerf Channel 1/8" x 3/8"