Rislone® High Mileage Compression Repair with Ring Seal is a concentrated proprietary blend of high-shear and premium polymers developed for higher mileage engines that are suffering from decreased or uneven compression. Low compression can be caused by normal engine wear and decreased sealing between the piston rings and cylinder walls. The non-dispersant olefin copolymers fill scratches & grooves in cylinder walls to increase and stabilize compression in all cylinders. Compression Repair renews worn engines, rebuilds compression, restores lost power and repairs engine blow-by. In addition, Compression Repair helps vehicles pass emission tests. item: 4474