The BF 3V custom BlueFang battery provides lasting power to our exciting, new BlueFang Smart Phone Controlled Training, Bark Control and Containment Collars. This unique battery uses High Tech Pet's patent pending, dual voltage system that supplies 3 volts to the collar's processor and other low voltage components, while simultaneously providing 6 volts to the shock transformer and other high voltage circuits. The result is a very efficient power system that stretches battery life to the max. This ingenious collar power system is only available from High Tech Pet.