The D3I3740 from DiTom Microwave is an isolator that operates from 37 to 40 GHz. It has an insertion loss of less than 0.7 dB and an isolation of more than 18 dB. The isolator can handle up to 5 W of average power and 30 W of peak power. This isolator is available in a module with K-type (F) connectors.