[Premium Quality Replacement] Equivalent to PetSafe Model RFA-188 collar batteries. 10-year shelf life. No mercury and Cadmium. [Technical Specs] 3V Lithium Ion Batteries. [Compatibility] 100% compatible with PetSafe RFA-188 batteries; never popping out or falling out from the collars. [Frequency Of Replacement] Battery modules are waterproof and last 1-3 months, depending on use. [Trusted Brand] Made by PET STANDARD for a Better Fit and Better Battery Life [Friendly Customer Service] Please feel free to contact us if you have any questions about our products, we'd like to help you!