That is a large capacity machine, from the 1986 to 1990/1991 time frame. The differences in the tubs (capacity) are hard to see in a photograph because standard capacity was narrower but of generally similar height vs. the belt-drives that differed noticeably in tub height and diameter.
Dual Action agitators began in Kenmores in the 1976 model year in several 90-series machines including the Lady K and one 70-series standard capacity model. Each year for the next three or four years they found their way though the 80 and 70 series models. Finally by 1983 there was a 60-series with it.
The belt-drive DA agitator was largely unchanged, especially in appearance, but the original ratchet design was quickly replaced by the current design which had the 'dog and catch' design. The auger was shorter in the standard capacity machine, and was not commonly seen.
Gordon