Gator Grid GG 20-20, a biaxial geogrid, provides strength, longevity, excellent stress transfer and prevents failure to the internal structure of your staircases, patios, landing areas, retaining walls and steep slopes. As a biaxial geogrid, GG 20-20 has a high molecular weight as well as high-tenacity polyester yarns which are woven in tension and finished with a PVC coating.