A new breed of bicycle chain is the Rohloff SLT99. This is a German chain. The SLT stands for "Segment Lager Technik" because it uses segmented bearings within each roller of the chain. The bearings have a three sided, non-concentric shape that gives rollers added freedom of movement. This allows the rollers to adjust so they rest precisely on each gear tooth. Because the chain adjusts, it reduces wear on the chainwheel teeth, reduces friction and improves efficiency. It's a super narrow chain, only 6.85mm and can be used with even the narrowest freewheel with ease. The chain has nickel plated roller and pin link plates, with Black link pins. It comes with 118 links for Mountain or Road use, weighs 344 grams, and is the most expensive steel chain you can buy. $ Price in Catalog