The ETA 2820 is an automatic calibre from ETA.
Like the closely-related 2822 (date only) and 2828 (day/date) movements, the 2820 is an 11.5 ligne, 21,600 bph automatic-wound movement.
All members of the 2800 “family” are related, but this series is closest to the automatic 2800/2802/2808 line, which shares similar specs.