If you dog has been trained to wait patiently outside the door until you let it in, what happens when you’re not around the home or have fallen asleep? Well, Fido can let himself in thanks to the Pet Sensing Doorbell. This device consists of a smart key hooked to your pet’s collar which will activate a cordless doorbell and alert whenever it comes close to the sensor in your door, all without having it scratch your door or bark incessantly. The working range is adjustable between 6″ to 3′, and the tone will sound for approximately seven seconds, repeating itself every five to 10 seconds until your pet moves away. The Pet Sensing Doorbell will retail for $79.95 and comes with a maximum volume level of 101 decibels.