Simply Auto SB-23A 23A 12V Alkaline Car Key and Alarm Fob BatteryThe Simply Auto 23A Battery is different to other key fob batteries. Where most modern remotes run on a 3V coin cell, aftermarket car alarms, garage door openers and older remote fobs often need 12V to drive their radio transmitter far enough, and the 23A is how manufacturers get that from something barely bigger than a AAA.A 23A battery is 12 volts. It achieves that by stacking eight small alkaline cells in series inside one sealed steel casing, which is why it is noticeably heavier than it looks. It is a direct drop-in for anything specified as 23A, A23, MN21, VR22 or L1028; five names for the same cell, depending on which manufacturer's catalogue you are reading.Fitment is usually straightforward, since nothing else in the range looks remotely like it. Check the code on the old cell before ordering, note which end goes where, and take care not to short the terminals against anything metal while you are handling it. A 12V cell will spark where a coin cell would not.Beyond car alarm fobs and older remote fobs, the 23A also powers garage door openers, wireless doorbells, alarm system sensors, LED torches and remote-controlled toys.If your key takes a different cell, the full Simply Auto car key battery range covers the 27A and A76 alkalines plus CR1220, CR1616, CR1620, CR1632, CR2016, CR2025, CR2032, CR2430 and CR2450.