Material: Manganese steel clamp, spring steel compressor. Adjustable Sizes: 3 inch, Piston Ring Compressor: 53mm - 175mm. Damage Free: Perform engine rebuilds and use this compressor for proper installation of the piston and rings into the cylinder without bending or damaging the parts; perfect fit on the piston and a positive locking action to compress the rings and allow the pistons to be installed into the cylinders. Applications: Suitable for small engines such as push mowers and lawnmowers, large enough to be used in tractor pistons. Package includes: 1x Piston Ring Compressor, 1 x Piston Ring Pliers, 1 x Wrench