The bark collar for small medium large dogs with 7 sensitivity levels. 3 basic training modes of beep, vibration, and shock, provide 64 kinds of training methods. Protection function, two silicone sleeves can protect the dog's skin from electric shock. IP7 waterproof bark collar which can be used indoors and outdoors. Bark collar rechargeable, charged in only 30 minutes and works for about 12 days.