This is amazing! They fit perfectly and cover the entire metal part of the precious stem. These are real cases with a plastic insert to hold the threads and appear to be of pretty good quality. My only complaint would be that they don't match. One of them has a silver primer and the other three have gold, I don't really care but I'm sure they will really bother some others. Edit: After seeing my review, the seller contacted me about the mismatched cases. . They sent me a new set for free, everything arrived. So not only is this a great product, but the company also offers great customer service.