What is that plastic plate with all of the holes on the agitator for? Is it a filter? Something for delicates? What?

I think you're right,it's a filter.

kennyGF

I should add,I've always seen them under the agitator.

Now that I think about it you are right GF

That Grate goes over the agitator drive shaft, UNDER the agitator. Its called a "Sediment Trap".
"It traps insoluble particles of dirt and lint, prevents them from being redeposited in clothing."
I have this exact machine, works great!

Rich

Actually ... that is called a strainer and powerfin64 is correct in that it resides under the agitator. The sediment trap, however, is the part that would be under the strainer when the strainer is placed on the machine properly. The sediment trap is actually the top of the center plate of the machine.

The strainer was only used on pump models to keep large articles (buttons, zippers, coins, etc.) from going down the drain hole and into the pump where it would damage the impellers.

The strainer does not work well as a lint filter. Maytag actually made a lint filter agitator for their wringer washers in the 1960's. It wasn't very popular. I have one and it works well when I do blankets and other "linty" items.

These were great wringer washers!