Liftech uses polyurethane foam systems to lift and stabilize sunken or uneven concrete. The process is completed through a 5/8" hole drilled in the surface of the affected concrete. High density polyurethane foam is then injected through the hole lifting and stabilizing the concrete. The small hole is then patched and blends with the surrounding concrete. The process can be used on driveways, walkways, patios, stairs, or floors. Get rid of those ugly tripping hazards in minutes, not days!