Product review (3 stars): You have to add a washer to prevent the knob from breaking again.
Still has the same defect that caused the need to replace the first one.  If you're looking at this, you likely are replacing it because the plastic sleeve that holds the knob on has cracked.  This is exactly the same.  To keep this from hapening again, I went out and got a washer with an inner diameter that exactly matches the plastic sleeve.  I don't have the dimension beacuse I just picked the washer out of the drawer of washers I have, but if you take this to the hardware store, you can find the right size washer.  You can slip(pound) the washer on the very end of the plastic sleeve, and this will reinforce the knob such that it doens't break again.  Still annoying to have to fix a new knob, but it needs to be done due to the design error.