D.I.D’s PATENTED X-Ring construction reduces friction by twisting between the side plates instead of being squashed. Normal O-Rings and other makers’ modified O-Rings have squashed points that increase friction. The twisting action of the X-Ring disperses the pressure and minimizes power loss.
Chain Specs: http://www.didchain.com/chainSpecs.html
EK’s exclusive CRH pin treatment provides an extremely hard outside coating and softer inside to increase strength and reduce chain wear. The Chromium Carbide pin surface coating also offers superior impact and shock absorption while reducing oxidation caused by natures elements.
EK’s screw type master links do not require any special
tools for installation. This unique patented link gives a rivet-like
fit, using only an 8mm wrench and a pair of pliers.
Chain Specs: http://www.ekchain.jp/product/pdf/cartalog_01.pdf