The WR28-KFR+ from Mini Circuits is a Waveguide to Coax Adapter with Frequency 26.5 to 40 GHz, Insertion Loss 0.15 to 0.40 dB, Operating Temperature -40 to 85 Degree C, Storage Temperature -55 to 100 Degree C, Weight 54 g. More details for WR28-KFR+ can be seen below.