Button cell battery. These small batteries are used in small electrical equipment like the calculator in the background. This is an alkaline button ce Stock Photo - Alamy
Solar-powered calculator - Wikipedia
Calculator 12-bit Solar Cell Basic Calculator Solar Battery Dual Power Office Calculator with Large LCD Display and Large Button Without Battery Suitable for Everyday Basic Office : Amazon.in: Office Products
SagaSave Mini Pocket Calculator 8 Digits Display with Button Cell Plastic Portable for Schools Homes Kids - Walmart.com
Tia LR-44 1.5v Alkaline Button Equivalent LR44 A76 AG13, G13A SR1154 357 for Calculator, Toy Cell Battery 0% Hg -20 Pieces : Amazon.in: Electronics
Tia LR-44 1.5v Alkaline Button Equivalent LR44 A76 AG13, G13A SR1154 357 for Calculator, Toy Cell Battery 0% Hg -20 Pieces : Amazon.in: Electronics