Park Tool 687 Reamer Stop Description: The Park Tool 687 Reamer Stop works with Park Tool HTR Reaming and Facing Sets to safely clean up press fit bottom bracket and headset interfaces within a frame. This stop replaces the facing bit so the outboard surface on the frame is not worked on, and creates a natural stopping point for the reaming process so the surface is cleaned up only to a prescribed depth to avoid removing too much material. This stop's 57mm diameter safely interfaces with any bottom bracket or headtube size, and the rugged materials and precise machine work ensures a long useful lifespan even when heavily used in a bike shop. Features: Replaces the facing cutter on Park Tool Heat Tube Reaming and Facing sets when only the reaming function is needed for a head tube or press fit bottom bracket shell Stops the reaming process at the prescribed depth without machining the outer surface Rugged construction ensures this tool can hold up to heavy bike shop use and abuse 57mm diameter provides surface area to properly fit up against any press fit bottom bracket or headtube opening Compatible with Park Tool HTR-1, HTR-1B, and HTR-HS Reaming and Facing Sets; Reaming and Facing sets are available separately