Bests & Worsts Reviews from Amazon

This is my third unit. The first unit died after four years of outdoor use. I mounted it under the eave of my house and aimed it at my neighbor's back porch. Their two dogs stopped barking at each other in a few days. The older dog took longer to finally quit barking at squirrels. Bought a second unit for my daughter for her new house. Her results were better. The dog next door would bark at anything that moved both day and night. She mounted the unit in a tree near the fence. The first night, the dog barked all night long. When she got home from work the next day, the dog was silent. Quick learner. Bought the third unit to replace the first unit which died of old age. Told my doctor about the bark control unit. She ordered herself one immediately. I use L-ION rechargeable batteries as the unit is more powerful than others and require more powerful batteries. Bought four L-ION batteries plus L-ION chargers. My daughter changes out the battery weekly. She used a battery connector to extend the battery leads to where she could reach from the ground. Does not have to climb the tree weekly. I wired my charger to connect directly to the unit via a L-ION battery. Totally automatic. All dogs may not have good hearing. If not, ultrasonics may not be as effective.