Quantic PMI Model No. HP-26D5G-40G-CD-292FF is a High Pass Filter with a passband of 26.5 to 40.0 GHz. It has an insertion loss of 1.1 dB, a rejection of 67.76 dBc, and a VSWR of 1.8:1. This unit has 2.92 mm female connectors and is 0.65" x 0.65" x 0.50" in size.  https://www.pmi-rf.com/product-details/hp-26d5g-40g-cd-292ff