The BBP-AOS is used in conjunction with the BBP-1.2 Bottom Bracket Bearing Press Kit to extract press fit bottom bracket bearings, cups, and adaptors. The BBP-AOS utilizes an expanding collet and extractor cup system to safely remove bearings without requiring impact. Also included are eight installation drifts for pressing bearings into pre-installed cups. - 8 precision-machined extractor cups and 5 hardened collets for compatibility with most bearing IDs and bearing/cup ODs - 8 installation drifts for standalone bearing installation - Organized in a convenient storage case - Full list of compatible bearing inner/outer diameters found on instructions/parts diagram NOTE: The BBP-AOS requires the BBP-1.2 Bottom Bracket Bearing Press Set for use. The BBP-1.2 and BBP-AOS are also available as a complete set (part # BBP-2).