The AE18000SSH6577 from Anatech Electronics is a suspended stripline high pass filter with a cutoff frequency of 18 GHz. The filter has an insertion loss of less than 2 dB with a rejection of more than 60 dB from DC to 16 GHz. The AE18000SSH6577 can handle a power of up to 15 watts. It is available in a module that measures 18 x 16 x 10 mm with SMA female connectors.