Teeth on the transition washers penetrate aluminum and copper oxides, enabling copper to aluminum connections to be made in a bolted joint without the use of inhibiting compoundsTransition washers also accommodate the difference in thermal expansion between copper and aluminum and enhances the efficiency of bolted grounding connectionsLower installed cost - no need to grind aluminum surfaces, apply compounds or use spring type washersQuick, dependable and versatile540 to 730 in-lb bolt torqueFits 5/8 in bolt size