T47 is a newer bottom bracket shell design, utilizing the oversized interface of PF30 and EVO386, but with the benefit and peace of mind of a threaded interface.This BB allows you to install Quarq and SRAM 24/22mm spindled cranks into a T47 frame.There are 2 versions:Standard and Coated Bearings.CeramicSpeed bearings come installed in cups and are connected through the shell.Both have super round CeramicSpeed balls and hardened-steel races.The Coated have an additional attribute:a 3-micron thick metallic layer over the races.This addition makes the races harder and smoother, lowering drag and increasing life.