Nukeproof horizon top headset cupthe horizon top headset cup from nukeproof comes from a new range that uses titanium coated race bearings with stainless steel balls. The titanium coating is applied using ldquophysical vapour depositionrdquo which means that the material is vapourised in a vacuum environment and then deposited on the bearing races as a composition coating.this process allows the structure, density and stoichiometry of the coating to be controlled allowing the exact attributes in our design brief to be achieved. The coating is 0.000118rdquo thick and has a molecular bond to the bearing races so it wont wear off or corrode. The bearing is abec 5 certified which means that it has passed tests which include id and od tolerances, roundness of ball, the trueness of faces surfaces as well as noise testing at high rpm making it the perfect bearing for use in a headset.these bearings have been designed for use in the harshest weathers and have gone through various tests by the nukeproof team during development so they are 100% confident in their performance. To back this up nukeproof are offering a 5 year warranty so you can rest easy knowing your purchase will be a good investment. Features headset type specific top cupbearings replaceable, angular contact type graphics laser etched finish hard anodised options internal and external includes top cap and bolt supplied modelheadtube internal diametersteererblack ex34 28.6 t1 1.1 8 top cap included34mm1 1 8black zs44 28.6 t2 1.1 8 top cap included44mm1 1 8black zs49 28.6 t3 1.1 8 top cap included49mm1 1 8 buy nukeproof components from chain reaction cycles, the world's largest online bike store.