If you’re looking to install your new Big Cat Flap in a glass door or window, we’ve got you covered with this installation adaptor. Designed to work exclusively with the new version of the Big Cat Flap, this adaptor comes with a circular glass cutting template and hardware for installation. Please note that the cutout in glass must be done by a professional glazier and cutout must be done at the time of door manufacture for multi-pane and tempered glass. Your pet deserves the best. Trust PetSafe® to keep them healthy, safe and happy.