Budget Watch Collecting/Watch battery interchange
SR=Silver Oxide LR=Alkaline. Silver can always be substituted for Alkaline, with a longer life. In some applications alkaline will not substitute for silver.
Older batteries made a distinction between low drain and high drain. Modern quality batteries can be used for either.
| AG | silver | alkaline | Timex | |
| AG0 | 379 | SR521 | LR521 | JA |
| AG1 | 364 | SR621 | LR621 | T |
| AG2 | 396, 397 | SR726 | LR726 | N,V |
| AG3 | 392 | SR41 | LR41 | K |
| AG4 | 377 | SR626 | LR626 | BA,MA |
| AG5 | 393,309 | SR754 | LR754 | C,F |
| AG6 | 371,370 | SR920 | LR920 | Z |
| AG7 | 395,399 | SR927 | LR927 | W |
| AG8 | 391 | SR1120 | LR1120 | LA,L |
| AG9 | 394 | SR936 | LR936 | |
| AG10 | 389 | SR1130 | LR1130 | M |
| AG11 | 362 | SR721 | LR721 | S |
| AG12 | 386,301 | SR43 | LR43 | D,H |
| AG13 | 357,303 | SR44 | LR44 | A,J |
| 343*, 344 | SR42 | B* |
*1.35v mercury battery, no longer made--Silver and Alkaline are 1.5v, usually work.
Note: If you've got more interchange information feel free to add it as plain text, someone will come and format it later.