Internal Assembly Semi Cartridge (I.A.S.C) Bottom bracket system allows for 19mm axles in Euro (BSA) type threaded BB shells.Compatible with BMX type crank sets and most other similar sliding 19mm axle crank systems.The patent pending Gusset I.A.S.C bottom bracket system installs easily with a UN type tool to give optimised bearing adjustment and additionally forms an effective dirt and water internal shield.The I.A.S.C system is also fully serviceable and also allows easy replacement of the individual Industrial cartridge bearings as required.FeaturesForged Cr-Mo UN style steel BB cups.Variable, sliding chainline.4 replaceable industrial cartridge bearings.I.A.S.C System optimised bearing adjustment.Weight: 246g (inc. spacers)