RR601 | 6 lb. Foam You should never settle, except when it comes to HMI’s RR601. RR601 polyurethane concrete raising and soil stabilizing foam was specifically engineered and formulated as a special request to us from D.O.T. engineers. RR601 is a 6 lb. per cubic foot density foam developed especially for infrastructure repair. The increased compressive strength is well suited for substantial loads and high traffic. » Request a technical data sheet for RR601 » Read the RR601 Case Study Want to learn more about our revolutionary soil stabilizing poly foam? Get in touch with us now!