With the addition of a K&H Pet Products Pet Bed Warmer, any cat or dog bed can provide comfort and warmth to your pet. It can be placed inside virtually any pet bed and is easy to use. Just plug it in! It will become your cat or dog's favorite place to nap. Dual thermostats regulate temperature using very low wattage. The heater is set to keep the surface temperature of your pet's bed 12° to 15° above ambient air temperature when your pet's not in the bed; then it automatically warms to a pleasing 102°F when the pet lies upon the bed. K&H Pet Bed Warmers are tested & certified by MET Labs and exceed USA/CA electrical safety standards; K&H doesn't just use safety listed parts, we safety certify the entire product - For indoor household use with 110/120 volt electrical current only. NOTE: Do not use Pet Bed Warmer alone, must always be placed inside a pet bed. Not for outdoor use.