The LCAD30018 from L-COM is a In Series RF Adapter with Frequency DC to 4 GHz, Contact Resistance 1.5 MOhms (Inner Conductor DC Resistance), 1 MOhms (Outer Conductor DC Resistance), Insulation Resistance 5000 MOhms, Temperature -65 to 165 Degree C, Voltage Rating 500 Vrms. More details for LCAD30018 can be seen below.