Manufactured by Olivetti (AT&T acquired a stake in Olivetti in 1983, thus becoming a subsidiary) the AT&T 6310 compact electronic typewriter is a re-branded variant (I think) of the Olivetti CT-605 …
According to ribbon listings the following Olivetti-derived AT&T models were available:
AT-30, 5300 (Portable), 6100, 6110, 6200, 6210, 6300, 6310, 6400, 6500, 6510, 6610, 6710, 7500, 7500S, 7510, 7510S
Electronic Typewriter Instruction Guides
The following guide is freely shared. A small donation, however, will make it easier for me to continue to add to this archive. Thank you!