The 648L is an M47 x 1.0 left-hand threaded standard guide for use when facing bottom bracket shells with the BTS-1 Bottom Bracket Tapping and Facing Set or BFS-1 Bottom Bracket Facing Set. This guide is used on the drive side (right side) of the bike.

• M47 x 1.0 left-hand threading
• Sized for T47 bottom bracket shells
  

NOTE: Always use cutting fluid such as Park Tool CF-2 when machining.