Park mlp12 master link pliers an updated version of the original and best selling park master link pliers many non shimano derailleur chains use a master link that allows the chain to be installed and removed by hand while this type of master link doesnt require a traditional chain tool over time dirt and corrosion can make it very difficult to separate by hand mlp 12 master link pliers have cleverly redesigned tips allowing them to be used to rejoin stiff or corroded master links