Pet Contech StayAway Motion-Activated Pet Deterrent, sensor, circuit, sensored, alarm, detection Supply Store/Shop Humane method of keeping pets away from certain areas of your home Passive infrared sensor detects animal within 3-foot range Two different modes of operation: sound with odorless compressed air spray and sound only Each replaceable can of compressed air holds over 200 sprays Powered by 4 AAA batteries (sold separately)