Marketing InformationSioux Chief 525-3 series MainBlock shall be used when necessary to rigidly secure CTS water main when penetrating a slab. Pipe clamp shall mount to the surface of a wood or metal stud. Clamp assembly shall include two block halves. One block half is sized specifically for 3/4", 1" or 1-1/4" CTS that is fastened directly to a universal rear block. Approved hardware shall be included. Main Block shall be compatible with copper, CPVC, PVC, or PEX tube.