This is a KMC "Drop Buster" chain - stretchproof chain with mushroom rivets and thicker side plates.
* 1/2" X 1/8
* Copper (not as light as the stuff coming out of Japan - this looks like a one or two year old American penny)
* Model number is Z510HX
* 113 links
* Comes with built in offset link and master link (both of which are NICKEL - not the copper finish)
* Great stretchproof chain for any single speed application (BMX, Fixie, cruiser, etc.)