Humane and harmless to your dog. Generally recommended for medium dogs. Don't recommend for too small dogs, like less than six months old. Safety precaution.
Collar will beep twice before shock. You have enough time to stop using it, if your dog feels uncomfortable.
The next 5 times shock intensity will gradually increase, you could stop using collar to aviod too higher intensity .
After the stimulations repeat through 7 correction levels, collar will be into a sleep model for a minute to protect dogs. You could stop using collar, if it is ineffective for your dog.
Use plastic probes instead of metal probes, then collar will not shock your dog at all. (Not include plastic probes in package).