Lant KTM Z-Ring 520 118 zale Orange The Z-Ring has 4 contact points in contrast to 2 contact points with O-Ring chains. This means higher flexibility and better running characteristics for the Z-Ring chain. The spring effect of the Z-Ring guarantees consistent and permanent lubrication. This means a significantly longer service life for the Z-Ring chain. â€‹This chain provides a better seal against penetration by water and dirt.