The STO-10203-U6 from ERAVANT is a Vector Network Analyzer Extender with Extended Frequency 75 to 110 GHz, Input Frequency 12.5 to 18.33 GHz, LO Frequency 12.5 to 18.33 GHz, Output Power 5 dBm, Input Power 0 to 6 dBm. More details for STO-10203-U6 can be seen below.