Michael Rogers, Vice President Communications for the Small Business Association of Michigan, talks with Jacob Monthei, General Manager of Redi-Rock International of Petoskey, a member of the Michigan 50 Companies to Watch. Redi-Rock large block retaining walls are built using massive, one-ton blocks to hold back the earth. Each one-ton block installed equals nearly 6 sq. ft. of face. This means that large block walls can be installed in a fraction of the time it takes to install a small block wall.