SGM Security Polymer® SGSIL121 25 lb Bag #121 Silver Grout. SGM Security Polymer Grout is a polymer-modified Portland Cement-based grout designed to be used with all types of tile in joints from 1/8″ to 5/8″. Recent polymer innovations have made the need for liquid additives a thing of the past. SGM Security Polymer Grout eliminates mottling while being easy to clean up, is non-shrink, and incredibly strong. Our Security Polymer Grout is suitable for use in both commercial and residential applications, with all types of tile, marble, granite, and slate. Additionally, it’s a great fit in service areas such as showers, countertops, walls, floors, schools, kitchens, hotels, and hospitals. Ideal for use in swimming pools, spas, fountains and submerged applications.