It doesn't work for me and I should have reviewed the specs first. The noise coming out of this little box is 80db. Here some common noises that are about 80db:Garbage disposal, dishwasher, average factory, freight train. Car wash at 20 ft (89 dB); propeller plane flyover at 1000 ft (88 dB); diesel truck 40 mph at 50 ft (84 dB); diesel train at 45 mph at 100 ft (83 dB). Food blender (88 dB); milling machine (85 dB); garbage disposal (80 dB).So if your dog is a stubborn species don't buy it.