What's the point in having an alarm if it doesn't go off in an emergency? Where safety is concerned, compromise is not an option. It's a good thing that Duracell Security have got you covered! This 12V MN21 battery is designed to fit in car alarms, key fobs and other key electrical devices. It is made with the same consideration and attention to detail as all Duracell products, with impressive battery life so it'll still be working when you need it most! 12V Duracell MN21 battery for car alarms, key fobs etc Impressive battery life and high levels of consistency Safety tested to prevent leaks When it matters, you can count on Duracell Safety counts. Don't compromise on quality Pack of 2 batteries