I have used this chain splitter on two bikes, one with an o ring chain and a push master link and the other with a non o ring snap link chain. In general it works very well. I found that I couldn't apply enough force with the short handle when mounting the connecting pin on the O-ring chain. I ended up using a wrench on the switch body to get the necessary leverage. The product is strong enough not to break. This is one of those tools that you can buy once and use forever. Anyone who does maintenance work themselves should have this tool. It comes in a nice carrying case and has easy to follow instructions that fold neatly into the bag. new version.