The negative reviewers, obviously don't know how to use this handy attachment.It comes with a hinged citrus cover, for good reason. You place the fruit over the juicer, and lower the cover; sparing any contact between your hand, and the spinniung extractor. Gentle pressure is all thats required to fully juice any piece of fruit. If you're getting rind, simply stop the machine, re-orient the fruit, and continue. Its also got 2 spindles, for larger, and smaller fruit. As was mentioned, trying to do key limes(which are only about the size of a golf ball), well, there are more appropriate tools, as they are exceedingly small. Try a lemon reamer. Does wonders for anything from lemons, up to giant sized grapefruit. I use it all the time.