Product review (3 stars): Great after husband fixed it
As mentioned by another reviewer, on the replacement part, the screw piece wouldn't screw onto the dishwasher. The diameter of the threaded piece is actually smaller on the new part!

My husband snapped the new spray arm onto the old screw piece, using the new, 3-prong fastener that came with the new part.

After it was fixed, we took part #s off the old part and searched again to see if we just ordered the wrong thing. Nope - the old part # leads directly to this one on over a dozen appliance sites. Too bad it isn't a good fit!