Pretty Easy & actually fool proof.....there are other similar tools out there, since it's a pretty basic concept. Check ebay, also Eastwood has a similar tool. Some dents will take repeated passes until you're satisfied - I say satisfied because the dent may not always disappear completely - more often than note you're going to be minimizing the ding than eliminating it. The best ding I removed with this tool was on my motorycycle's gas tank - it popped-out completely on one pass, and although no one else could notice it I noticed a minor "wave" in the tank's rounded sheetmetal where the ding used to be.....nothing big, but you had to really focus on it to see it. I ended-up ordering several dent/ding removal tools(hand dolly hammers, "blood pressure sleeve"-like inflatable bags) from Eastwood so I can pretty much tackle anything.
