Abstain your pet from barking unwantedly with this advanced bark stopper. The ultrasonic device detects the dog snarling up to twenty feet away and shoots a wave that holds the animal from excessive barking. Features:. Stopper has an LED working indicator light, low and high volume. Works up to 20 feet of range. Harmless to dogs with no electric . Compact design slides into a holder with wall mount holes. Instructions included on back of package. Requires 1 9V battery (not included). Comes packaged in a clam shell Dimensions: 1.875"H x 1.25"W x 5"D. Material(s): plastic Pack includes 4 of the item shown