Acros ai 47 is47 3033 lower headsetdesigned for smooth performance on your road bike or mountain bike, this lower headset gives you a rotatable interface between your bike's fork and headtube. It features a hard wearing aluminium construction, which makes it capable of handling the abuse associated with shredding the trails or competing in a road racing event. Acros has also gone the extra mile, by equipping this lower headset with stainless steel bearings and an r3 seal for top performance in all weather conditions. Features headset material aluminium bearing material stainless steel seal material r3 metal reinforced rubber use road, mtb steerer diameter 1 1 8 1 1 4 tapered bearing fit 47mm headset type integrated part number 4502601s weight 35g approxbuy acros components from chain reaction cycles, the world's largest online bike store.