Vinnic L1325, RFA-18, A28PX, 4LR44, A544, PX28A, 4G13 6V Alkaline Battery for Dog Collars and Barking Control Systems - GN Batteries & Electronics Inc.
Amazon.com: Energizer A544 6-Volt Photo Battery 10 Pack with Cloth : Health & Household
Amazon.com: PKCELL 4LR44 GP476A 4A76 PX28A L1325 6V Battery Alkaline for Dog Collar (30pc) : Health & Household