A tool kit for those who like to dig into engines, it consists of 8 pieces for working with piston rings from Mardatt. Believe me, this thing can make engine repair a lot easier. You can easily compress and install piston rings without any trouble. There are three piston ring compression tools of different sizes - 3, 4 and 6 inches. They are suitable for almost any automobile engine. The largest one can handle pistons from 60 to 195mm in diameter. These piston ring mandrels are made of nickel-plated spring steel, they are strong, do not rust and last a long time. The set includes special pliers for piston rings. They are made of chrome vanadium steel and have a built-in spring. This makes them flexible and easy to use.