The UltraSIL design from Cooper Power Systems incorporates a housing of polymer material (silicone rubber) which is an excellent insulator of overhead products, delivers high UV resistance and high hydrophobicity. The UltraSIL design delivers superior performance in distribution- and station-class surge arresters and cutouts. For long term weathering performance, water repellance, resistance to UV degradation and atmospheric pollution as well as other important insulation performance, silicone rubber is unsurpassed.