9 ELECTRICAL CONTACTS, ELECTRICAL SLIDING CONTACTS OR BRUSHES, ELECTRICAL CURRENT-BREAKING CONTACTS, AND CONTACT ELEMENTS FORMED OF NON-PRECIOUS METALS, PRECIOUS METALS, BI-METALS, TUNGSTEN, SINTERED GRAPHITE AND METAL, AND GRAPHITE
THE MARK CONSISTS OF THE LETTERS "D0" OVERLAPPED AND ANGULARLY DISPOSED, AND APPEARING IN A CIRCLE. THE LINING SHOWN ON THE DRAWING IS FOR CONTRAST PURPOSES ONLY.