The 691 is a 1.370" x 24 TPI right-hand threaded tap designed for use with the BTS-1 Bottom Bracket Tapping Set to tap English threaded bottom bracket shells. This tap is used on the non-drive side (left side) of the bike.
Features
- 1.370" x 24 TPI right-hand threading
- Sized for English bottom bracket shells
- NOTE: Always use cutting fluid such as Park Tool CF-2 when machining.