Joist hangers are designed to provide support underneath the joist, rafter or beam to provide a strong connection. Simpson Strong-Tie offers a diverse line of hangers to handle almost any application with top flange, concealed flange and field-skewable and slopeable options. The SUR/SUL are 45-degree-skewed hangers designed to support solid sawn and engineered wood products used in wood construction. The SUR and SUL hangers are identical except that they are skewed 45-degree to the right (SUR) and the left (SUL), respectively.