... bezel, brass bezel, steelroll ring (or bayonet threaded ring), type: snap on, roll ringTUBE&SOCKET: steel with nickel plated, phosphor bronze ... bezel, brass bezel, steelroll ring (or bayonet threaded ring), type: snap on, roll ringTUBE&SOCKET: steel with nickel plated, phosphor bronze ... 2.5%,1% accuracy, recalibrators,restrictors, special connections and more. Back Connection Steel Case Gauge 4Z2