I recently bought a heavy duty chain from KMC, the K710, and discovered my old chain tool/chain breaker was too weak to push the rivet through the chain links. The weak tool was a throw-away from Park Tools that had a tiny handle and the pin bent before the rivet budged. I needed a new chain tool that wouldn't frustrate me and was more durable and effective then my previous chain tool.I purchased this chain tool figuring KMC chain tools should work with KMC chains, which turns out to be true. Long story short, this tool worked beautifully. It is well constructed and feels very solid. The long arm generates lots of torque and while it takes some muscle to push the rivet, it was not a struggle. I really like that the pin is reversible and replaceable, unlike my old tool, so if the pin ever does bend it can be replaced without replacing the whole tool. At $35 it is at the higher end of chain tools, but this worked so well for me I am happy I took the plunge. I also feel like it will last a life time given it is built so solidly and I can replace the pin.In conclusion, sometimes to get the job done you need the right tool. For KMC chains this is the right tool.