After reviewing the course section on Stems and Sleeves it looked like the sleeve was easily removed and reinstalled. However, when I purchased a complete stem and sleeve, the sleeve is not easily removed as in the video. Not only is it very difficult to remove from the stem but it is almost impossible to put back on. I now know that if the stem is too long, I can grind down the length of the square part. If you need to replace the stem on a pocket watch, I would recommend finding a complete stem, that is with the sleeve attached. Some stems are listed by the case manufacturer but not all cases are listed. Some are listed as Tap 0, Tap 1, or Tap 2. Honestly, I do not know how to determine which Tap matches the one being replaced, or what it is referring to. If anyone knows what these refer to or how to measure for it, please post a reply to this post.