Although it can accomodate 16 mailboxes, do the math. 120 minutes total storage, divided by 16 mailboxes, gives you a grand total of 7.5 minutes of storage per mailbox. Not a lot!. So it's always been marketed as a 12 box voice mail. You can set it up for fewer boxes and gain more per box storage.
And the phone brochure shows the discontinued 9040 cordless.
