CR2025 batteries are standard 3 Volt lithium batteries, commonly used in watches, cmos, car keys, electronic toys and calculators.The CR in the phrase 'CR2025 battery' means that it is 3V lithium manganese dioxide. The 20 means the battery is 20mm in diameter and the 25 means the battery is 2.5mm in thickness. We stock many different brands of CR2025 batteries from the world's leading manufacturers.