Psusa Wisewire® Phoenix Rechargeable Invisible Fence Compatible Battery 2 Pack White

In simple terms, this means lighter batteries with increased run times. Replacing batteries not only provides the ability to instantly renew the collar receiver's power supply, it also provides a consistent duration for battery life. Lasts up to 20 days on a 4 hour charge Recharges up to 500 times for a 20 year life expectancy LED indicator displays when battery is completely charged Smart charging system senses battery charge and only charges up to capacity before switching to a trickle charge.