I've had four different cell phones with the same company, and for some reason the batteries that came with these phones didn't come close to the rated standby and talk times. In fact, the one that came with my current phone drops in power after less than 24 hours of standby time. I don't know, maybe they put used batteries with their new phones.But this one bought from Amazon for the Audiovox 9100 phones (9155 is the one it's being used in), comes closest to the published rated useage times.Maybe amazon has a good batch in their inventory.