This collar works wonders, best 30$ ever spent! My 1yo 81 lbs german shepherd use to run away as soon as we opened the garage/front door. It just took 1 time with the collar on and now she just stands beside me with no leash. Be aware that the shock level should not exceed 49% or your doggo will feel pain. For now on the vibration mode is all i use since shocking is not longer needed.