The PetSafe 3 Volt Module RFA-188 Replacement Battery (S55) is a high-quality battery designed specifically for PetSafe electronic fences. This replacement battery is compatible with the PetSafe RFA-188 model, ensuring a perfect fit and reliable power source for your pet's training and obedience system. With a long-lasting charge, this battery allows you to trust that your dog's electronic fence will continue to function smoothly and effectively.