Product review (5 stars): Fit my GSC3500D51WW perfectly and fixed my leak
This adapter fits the coupler on my GE GSC3500D51WW dishwasher perfectly (and will work with several other models--GE has a parts finder on their website you can use to check, and I see some people even have luck with other brands). I was having a problem where the coupler was leaking water at the faucet and, while my dishwasher was still under warranty if that was the problem, I wanted to make sure it wasn't my faucet or something easy to change like this adapter. Lo and behold, replacing the adapter fixed the leak. (This one looks like it has two washers on the top, the topmost of which extends farther than the metal part of the adapter; when I took my old one off there was only one washer and it was well below the top of the adapter. I'm not sure how it could have possibly fallen out or gotten lost when connected to the sink the whole time, but something must have happened unless they changed the part.)

This might have been covered under the warranty, but I'm not sure what GE would have charged if the problem was actually with my faucet itself, so the slight charge for this (plus not having to arrange for them to come to my house) was worth it for me. Hopefully this problem doesn't keep happening, but at least this was an easy fix.