I've never owned a tool like this before, but decided to order one because I also ordered a nice watchband to replace my old one.  Fortunately, the new watchband and this tool arrived on the same day.  I immediately noticed that there were no instructions included with this tool.  Being fairly mechanically inclined, I quickly figured out how the thing works.  It took me less than three minutes to change watchbands, which I probably couldn't have done without this tool.  It's a tool that I won't use very often, but it will be nice to have if and when I ever change watchbands again.  However, I certainly don't need 3 of them, so I'll give the other two to my daughters.