If you, like me, wanted to know the difference between this chain, and the retail Oregon S62 version that they sell in the stores, I have found a few "minor" differences, but, for the most part, are the same. When you see S62, from what I read, S just means that it is retail.. 62 is the number of links in the chain. The differences between the S62 (retail) version, and the 91PX062G (non retail) version are.. The S62 version comes in plastic packaging, has a link in it with the "S62" number on it, so you can remember which chain number to buy (this chain is usually gold in color), and costs more.. The 91PX062G model comes in a cardboard box, does not have that link with the model number on it, and is cheaper.. That is the only real differences I have noticed. I compared my old chain (many years old), and found that they have changed the design slightly over the years.. The non cutting link used to have a high spot on it, and that was removed, and a plain square link with no high spot replaced it.. I looked at the retail version, and the OEM "91PX062G " version, and both have the same non cutting link. If you have an old chain that has that, this one will work fine as a new replacement. Also, if you look at the pictures, my old one was sharpened multiple times, that is why it is more worn, and the cutting edge is smaller.. As for keeping the cutting edge. I immediately put this on, and cut up some wood.. It was used to cut some maple tree logs that were freshly cut, and were 10 to 12 inches in diameter.. I am guessing closer to 12". But, that log was cut cleanly though in 6 places, plus, some other stuff that was smaller, and it is still cutting as good as when I first put it on. The file needed to sharpen this chain is a 5/32", or, 4.0 mm 30 degree angle. This chain has a chamfer chisel design. It is the middle one in the picture of the back of the box. So far, no complaints.. I am including some photos so you can see the boxes, the info on the box, and, a comparison from their "old" version, to what they sell now.