"Dog Bark Deterrent DevicesDo you feel sorry that your dog disturbs the neighbor's sleep when you are asleep at night?You must be very reluctant to use a cruel electric shock way to train your dog to keep quiet.It's time to try our Ultrasonic Dog Bark Control Deterrents and gentlely say goodbye to those endless barking.Features:Defer noisy barking by harmless ultrasonic sound.Range up to 50 feet.Four adjustable ultrasonic levels (includes a test mode) Test - for verifying that the microphone and speaker are working properly. Low range-15 feet/5 meters (recommended for indoor testing) Medium range-30 feet/10 meters. High range - 50 feet/15meters.Hard shell and and weatherproof for outdoor use.LED light flashes for low battery indication.9V battery - (battery not included).