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: LiCB 10 Pack 4LR44 6V Battery PX28A 476A A544 K28A L1325 Battery 6V Alkaline Batteries for Dog Collars : Health & Household
Amazon.com: GoodBoy Bark Collar Batteries 5-Pack 6V Alkaline Battery 4LR44 (Also Known as PX28A, A544, K28A, V34PX) : Health & Household
Energizer Max 529-1 6V Alkaline Lantern Battery|BatteryJunction