The Park Tool CT-4.2 Master Chain Tool replaces the CT-4 Master Chain Tool. The CT-4.2 will work with “hour-glass” shaped 8, 9, 10 and 11 speed chains. Also fits the asymmetrical Shimano chain designs such as Dura-Ace 7900.
Specially designed to work with the tight tolerances and narrow profile of 10 speed chains and most high quality derailleur chains. The CT-4.2 is a powerful, precise tool designed to quickly and accurately remove and install chain pins. Without a doubt the most accurate chain tool we’ve ever built!