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
Set of 6 Grundig AG13/LR44 batteries (button cells, 1.55V) - Wood, Tools & Deco