Alkaline Keyless Entry Battery, #21, 12-Volt, 4-Pk.

Duracell COPPERTOP Series MN21B4PK specialty batteries are 12-volt alkaline batteries designed to power keyless entry systems, car remotes, and other small electronic devices that require reliable, long-lasting power. These batteries deliver dependable performance for security devices, remote controls, GPS trackers, and medical devices like thermometers and blood pressure monitors that rely on consistent voltage output.

When your keyless entry fob, car alarm, or remote control loses power, you need a replacement battery you can trust. This four-pack of Duracell #21 (also compatible with #23) alkaline batteries ensures you have backups on hand so you never find yourself locked out or without access to critical remote devices. Duracell's reputation as the #1 trusted battery brand means you can count on these batteries to perform when you need them most.

Features and Benefits

• 12-Volt Output: Meets the voltage requirements of most keyless entry systems, car remotes, and compatible specialty devices.
• Wide Device Compatibility: Fits #21 and #23 compatible devices, including car alarms, key fobs, GPS trackers, remote controls, and security transmitters.
• Long-Lasting Performance: Duracell alkaline manganese dioxide chemistry delivers reliable power for extended use in high-drain devices.
• Multi-Device Use: Works in medical devices (glucometers, blood pressure monitors, thermometers), toys, watches, calculators, laser pointers, and anti-bark spray collars.
• Duracell Guarantee: Backed by Duracell's manufacturer guarantee against defects in material and workmanship.

Specifications

• Brand: Duracell
• Model: MN21B4PK
• Battery Type: #21, #23 Alkaline Manganese Dioxide
• Voltage: 12V
• Pack Quantity: 4 batteries
• Equivalent Types: A23, MN21, 23AF, 23AE, V23GA
• Color: Black