Product review (5 stars): whirlpool ultimate care ii
Worked on whirlpool ultimate care ii washer.  I got 8557301B to replace 8557301A which is a revision update.  Washer is10 years old and when the  timer stopped spinning I thought I had to buy a new washer as I couldn't find the exact part number 8557301A.  After googling I found out that a revision update happened and after reading the reviews I was confident I was purchasing the correct part.  Amazon also was the lowest price for a brand new part.  One note was that the first shipment came broken.  The timer plastic tab was broken and the timer itself wouldn't pop up for the spinner.  Returned it to Amazon and got a replacement which worked correctly.