It's a Kenmore series 500 High efficiency/auto load-sensing. We got it two years ago, and from what I remember, the series 500 came in two different sizes, and we bought the bigger one. We got a big discount because our local Sears was going out of business, so I'm not sure if these are still available.What make and model do you have?
Here's the controls, and when doing horse blankets I put the middle dial on "bulky/bedding" the rinse dial on "two rinses" and the stain boost "on."
This is what the interior looks like, the outside drum turns at one speed, and depending on the settings, the outside bottom circle goes back and forth at its own speed and the mini-agitator on the bottom inside goes the opposite. It fits so much larger loads than what could fit in the same sized drum with an old-school tall agitator.
A bit of effort, but so much affordable than sending out my horse blankets to my local place.