The STO-1520305-T-E1 from ERAVANT is a Vector Network Analyzer Extender with Extended Frequency 50 to 75 GHz, Input Frequency 12.50 to 18.75 GHz, LO Frequency 12.50 to 18.75 GHz, Output Power 5 dBm (Test Port), Input Power 0 to 6 dBm (RF, LO). More details for STO-1520305-T-E1 can be seen below.