Product review (5 stars): Whirlpool Water Level Switch W10312527
<a data-hook="product-link-linked" class="a-link-normal" href="/EA-W10312527-Whirlpool-Washer-Water-Level-Switch/dp/B00APJD1NO/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">EA W10312527 Whirlpool Washer Water Level Switch</a>

Followed the advice found by earlier posters. Installed W10312527. Sliced off the end white alignment tab on the washer's plug.  It appears that the white plug contacts align a little toone side on the switch (versus in the middle on the original). (Don't drop it while reattaching or you'll need to take off the back to get it out! DOH!) I recommend attaching the hose first in case you drop it.

After installed got an F21 error.  Then removed and reinserted the white plug thinking that the contacts were not aligned correctly. Not sure if this caused it but washer works well now.

Note - I did not try one suggested solution before buying - Spray some electrical cleaner in the hose hole on the switch.  Someone on internet commented this worked for him.

Here is the part I bought - for $64.03 including shipping.
<a data-hook="product-link-linked" class="a-link-normal" href="/B0052DNBR4/dp/B0052DNBR4/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">B0052DNBR4</a>

See some helpful You Tube vids:
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