Abstract: An apparatus for making a dual seal insulator including an insert and a pair of elastomeric seals each united to one of the ends of the insert, wherein portions of the insert and the seals define a plurality of bores. The insulator is formed by mounting the insert in a mold to form a pair of mold cavities at each end of the insert and placing core pins in the bores of the insert so that they extend from the insert across the cavities. A keyway, disposed longitudinally on the circumference of the insert between the ends thereof, cooperates with the enclosure to define a passage between the mold cavities. An elastomeric material is pressed into one of the cavities so that a portion of the material is forced through the passage into the other of the cavities. In this manner, the pair of elastomeric seals is simultaneously molded at opposite ends of the insert. The insulator is then cured and removed from the enclosure and the core pins are extracted from the bores.