Park Tool Master Mechanic Chain Tool. Features: Specially designed to work with the tight tolerances and narrow profiles of 10 and 11-speed chains, the CT-4.3 is a precision tool that can be used to install and remove most 5 to11-speed derailleur chains Integrated Link Pocket ensures precise chain alignment Precision machined investment cast body and components with contoured cushioned handles Removable anvil to peen Campagnolo 11sp chains Not compatible with Wipperman chains Replaceable rotating pin (PK-7806) Specs: Description:CT-4/4.2/4.3 replacement pin kit, CTP-4K