Question: are a23 and a21 batteries the same?
Answer: The A23 battery (also known as 23A, 23AE, GP23A, V23GA, LRV08, 8LR932, 8LR23, MN21, L1028 or ANSI-1181A) is a dry cell-type battery mainly used in small electronic keychain radio devices, such as keyless vehicle entry systems, home security systems, garage door openers, and Bluetooth headsets.