GutAlkaLi LR44 Battery Pack of 20 – 1.5V AG13 Batteries for Watches, Hearing Aids, Glucometer, Key Fobs and Small Electronics – Silver Oxide Chemistry Provides Stable Voltage and Long Lifespan: Amazon.co.uk: Electronics
LR44 Battery: Equivalent, Specifications and Replacements
Battery Equivalent Size Charts - G&T's Original Warehouse