1.5V. AM-4PA/4B. Since 1921. Trusted quality. Protects power for up to 10 years (when unused and properly stored). Guarantee: This product is guaranteed to be free from defects in materials and workmanship. panasonicbatteryproducts.com. panasonic.ca/battery. panasonic.com/support. Made in Thailand. Packaged in the USA.