The UPI M-C-THANE Series and UREA-DEK SYSTEM 6500-RC elastomeric roof systems are based upon seamless, fluid applied, aliphatic polyurethane and polyurea coatings. These multi-layered roof coating systems are supplied with or without polyester or fiberglass reinforcement and are always topped off with a highly reflective aliphatic polyurethane top coat. These roof systems provide superior protection for new or remediated older existing rooftops. M-C-THANE 4556-75 MIL is a heavier-duty version than M-C-THANE 4556-60 MIL. M-C-THANE 4556-75 MIL would be recommended for use on a rooftop that experiences a high volume of pedestrian traffic while M-C-THANE 4556-60 MIL would be suitable for roofing surfaces with moderate pedestrian use.