The Simson Chain Derailleur 5/6/7 speed is a high quality bike chain suitable for bikes with 5, 6 or 7 (UG) derailleurs. This chain has 112 links and a size of 1/2"x 3/32". The chain can be customized using a Simson chain tool. Put the chain on the sprockets and close the ends of the chain together by snapping in the included connecting link.