3xlr44 3xag13 3xa76 4.5v Alkaline Button Battery Packs For Led Torch Laser Pen Alarm - Button Cell Batteries - AliExpress
Amazon.com: Tenergy 1.5 Volt Battery Button Cell LR41, ag3 Batteries Equivalent, Ideal for thermometers, Watches, Laser Pointers, Small Toys, Portable Electronics, and More - 20 Pack : Health & Household
LR44 Battery Equivalent, Voltage, Size, Uses & Life (FAQs)