The T47a 30mm Bottom Bracket is specifically designed for frames with a 77mm asymmetrical shell width, positioning the non-drive side bearing inside the frame and the drive side bearing externally. This threaded bottom bracket shell design utilizes the oversized interface of BB right, providing a secure and snug fit with the added benefit of a threaded interface. Equipped with precision dust covers, this hand-built bearing from CeramicSpeed guarantees exceptional performance without compromise. To ensure optimal installation, use the CeramicSpeed Dual Socket Tool and spacers, which are included in the box along with 2 cups, CeramicSpeed bearings and dust covers, a 2-part spacer tube, CeramicSpeed All Round Grease, and spacers for setup and adjustments.