The Park Tool 1971 Clamp Adapter installs onto the clamps found on most Park Tool repair stands to more securely hold D-shaped seatposts by converting one jaw profile to a flat surface. This is useful for bikes with D-shaped seatposts and other non-traditional designs that would cause a less-than-ideal fit in traditional repair stand jaws. The 1971 is designed to fit over a clamp’s existing jaw covers and is easy to remove and install by hand making it a convenient accessory for your repair stand.