Key Features:Differential headtube 45° x 45° ACB upper industrial bearing lower (for carbon fibre headtube)For differential OD headtubeUpper Angular Contact Bearings Lower Industrial bearingStainless crown raceCarbon top coverStack height: 9.4 + 0.9 = 10.3mmWeight 83.4gSpares:Top bearing: 160-6480Bottom bearing: 160-6740Crown race: H6083