Petsafe Underground Dog Fence Collar - For Stubborn Dogs - Waterproof Receiver - 5 Levels of Correction Plus Vibration - PRF-275-19 Bonus One 9 Volt The PetSafe Stubborn Dog Fence Collar should be used for dogs that are 20 pounds or larger Waterproof receiver. Also compatible with the Indoor Pet Barrier Transmitter (PIRF-100) to protect your pet indoors 5 Levels of Correction Plus Vibration. The most powerful receiver on the market Uses a common 9 volt battery providing a average battery life of 6-9 months. Low Battery Indicator Light - Lets you know when the batteries need replacing. One 9 Volt Included Compatible with PetSafe in-ground fences except UltraSmart Rechargeable In-Ground Fence (PIG00-13619) and YardMax Rechargeable In-Ground Fence (PIG00-11115)