Product review (5 stars): Hardest part in machine repair/maintance is removing the old nut. New nut is easy- Give new life to your machine
The Whirlpool 21366 Spanner Nut is a good value (when it saves you hundreds of $$$).  The piece matches the original spanner nut in the washing machine that I have. Not cheapo quality. It arrived quickly and good quality. It is what it should be: a spanner nut that fits my older early 2000's Kenmore Elite washer (model # 11016922503).

I was doing washing machine repair and maintenance- to keep my machine in top working condition (and to save myself from buying a new machine). I purchased this spanner nut in case I was unable to remove the original spanner nut that was on the agitator spindle for the past 12 years. I purchased a spanner wrench on Amazon (very happy with it and I reviewed it) and I was lucky enough to get the original spanner nut removed with the spanner wrench.
If I was not able to remove the original spanner nut it was going to be sawed off. Thus the need for a new spanner nut.
The new spanner nut that I purchased is now saved for when I will need to use it (or happen to fix another clothes washing machine that could use it).
My washer now works and is in just like new condition.

If you are doing DIY washing machine repairs, and need a spanner nut and if this suits your make and model of washing machine, you can buy this with confidence.