Product review (4 stars): As described. This knob fit my washer well but ...
As described.  This knob fit my washer well but had a metal ring on the back (around the post hole), which I'm sure adds some enforcement to the knob, but my dryer didn't have space for this metal ring to fit into the faceplate.  I ended up having to play 'musical knobs' to find one that fit.  In the end all is well.