215274 ⎘
Coupling devices specially adapted for supporting apparatus and having one part acting as a holder providing support and electrical connection via a counterpart which is structurally associated with the apparatus, e.g. lamp holders; Separate parts thereof; Dustproof, splashproof, drip-proof, waterproof, or flameproof holders for bayonet type coupling devices neither pole becoming electrically connected until the coupling parts are substantially engaged