The QCK-FL4G-D from Qualwave is a RF Connector with Frequency DC to 40 GHz, Operating Temperature -55 to 165 Degree C, Pin Diameter Dia. 0.3 to 0.75 mm, Voltage Rating 750 VDC, VSWR 1.15:1. Tags: Standard. More details for QCK-FL4G-D can be seen below.