SGM HSR 50 lb. High Strength Pool Render. SGM High Strength Pool Render is a cementitious blend of, proprietary admixtures and select aggregates. Engineered as a versatile and exceptional strength thin & thick bed render, HSR is factory blended to produce a consistent quality mix from batch to batch eliminating additional costly job-site additives. HSR is conveniently packaged in 50 lb. (22.7kg) polyethylene lined bags and custom palletized for easy handling and movement on the job-site. Use for bonded and non-bonded, conventional mortar bed where additional strength is desired. HSR is ideally suited for use as a render substrate for applications in wet areas. Use in place of Type S or Type N Mortar.