It is made of insulating silica gel material, which is molded at high temperature, and the connection parts of the transformer are integrally wrapped; the installation opening can be sealed with clips and lead seals of the power department, which has the characteristics of preventing personal electric shock and preventing short-circuit faults caused by small animals crawling; The product has reasonable design, simple structure, good dustproof and waterproof effects, thus preventing pollution flashover, wet flashover, preventing electricity theft in front of the meter, and preventing the loss of national power resources; excellent electrical performance, aging resistance, high and low temperature resistance, can be used under any conditions. It is suitable for power equipment distribution transformers, lightning arresters, outdoor switches, busbars and other terminal insulation safety protective equipment. It can effectively prevent the exposed terminals of electrical equipment from causing damage to power facilities and electric shock casualties due to various reasons.