This device is installed at the end of oil and gas and water transfer lines to prevent the electrical current injected into the pipes for cathodic protection.Among their specifications are electrical resistance over 4m with 1000V DC current and electrical fracture resistance over 5000V AC as well as withstanding high pressure .the dimension and designated and manufactured according to the standards in three groups of 150,300and 600 from 2 to 56" diameter.