Forged and CNC machined AL6061 thread-in cups for a superior fit and noise-free operation Low-friction dual seals protect the bearings from harmful contaminants Sealed premium bearings are both serviceable and replaceable Designed for installing Shimano HTII 24mm or SRAM GXP 22/24mm spindle cranks into BSA threaded frames 68/73mm ENG SRAM GXP 22/24mm AL6061 98g Black