Product review (5 stars): Literally saved me hundreds of dollars
My old Kenmore washer fit all the symptoms of broken coupling, wouldn't spin, but water functions were fine.  There are even audio clips you can listen to to help you diagnose the issue!  I watched a video and it looked easy enough.  This is the part where I tell you that I feel handy when I hang curtain rods or say, a picture.  So this was a big challenge for me.  I followed the video and verified that indeed, one of the brackets was completely cracked.  I ordered the replacement via Prime, and two days later my washing machine was working again.  It is definitely easier to remove the part then put it back in, but it still only took me about 30 minutes to carefully put it back together.

One note on putting it back together: I apparently didn't tighten something somewhere correctly, and the machine was jerking violently when it stopped spinning.  I removed the casing and double checked all of my work, and it worked perfectly after I did so.

My washing machine is old and will need to be replaced at some point I am sure-- but I like that this very affordable part can keep it running for who knows how much longer (knock on wood).