Magnetic plug and play system replaces four BB sockets. Included Pro BB Socket Cup and four Pro BB Inserts pack down to the size of one traditional BB socket toolFeatures a 3/8` square drive for use with torque wrenches, a 24mm external drive for use with Pedro`s Pro Socket Handle and pedal wrenches, and internal M12 thread for use with the Pro BB Socket Holder7075 T6 aluminum socket is fully machined to precise tolerances for an exacting professional-level fitInserts are precision laser cut tool steel with optimized heat treatment for precise fit and superior tool lifeIncludes Pro BB Socket Cup, and Pro BB Inserts: Shimano 16x44, BSA30/DUB 12x46, T47 16x52, & T47 12x52BB Kit64607693/8`UPC/EAN/GTIN: 790983298821