MOTTDAM 3 Pcs Watch Back Cover Removal Tool, Watch Repair Tool for Unisex-Adults, Modern Style Enthusiasts

I bought the set of 3 tools as I wasn't sure which one would remove the back of one of my watches. Turns out that the "knife" is the only tool which I need, so I can't comment on the effectiveness of the others. I'm not sure why the knife should be so much more effective than a penknife or kitchen knife, but it removed the back of my pocket watch in seconds, when other blades had failed to make any impression.

Great 3 piece set will do the task with ease not a problem.