PetSafe Staywell Pet Door with Clear Hard Flap Durable white plastic door with transparent, hard flap is perfect for single pet homes or moderate use U-flap system with magetic closure helps keep out weather and drafts Slide-in closing panel included to keep pet from using door, to close off opening when not in use and for an extra layer of weather protection Transparent flap is a great option for pets who want to check surroundings before using pet door Flexible installation in interior or exterior people doors 1/8" to 2" thick; Detailed instructions, cutting template and hardware included For Medium pets 40 lbs. or less; flap opening size 8 5/8" W x 9 5/16" H Call, chat or email with our expert US-based customer care specialists six days a week; they are waiting to assist you and your pet with your product needs PetSafe Brand is an industry leading US manufacturer of pet behavior, containment, and lifestyle products since 1991, helping millions of people and pets each year