Original Lectro-Kennel. Breeders, pet owners, and veterinarians have been using Lectro-Kennels to warm pets for more than 40 years. This new sleek, smooth design is now more comfortable and durable than ever! Constructed of rugged ABS plastic with a steel wrapped cord, the Lectro-Kennel can lie flat on the doghouse floor or be attached to the wall. An internal thermostat heats to complement the body temperature range of your pet. Lectro-Kennel also comes with a free removable, washable fleece cover. UL Listed. Indoor or outdoor use. One year limited warranty. Available in Small (12-1/2 x 18-1/2, 40 watts), Medium (16-1/2 x 22-1/2, 60 watts) or Large (22-1/2 x 28-1/2, 80 watts).