The 648R is an M47 x 1.0 right-hand threaded standard guide for use when facing bottom bracket shells with the BFS-1 Bottom Bracket Facing Set and 690-XL Oversized Facer. This guide is used on the non-drive side (left side) of the bike.
Specifications:
• M47 x 1.0 right-hand threading
• Sized for T47 bottom bracket shells