The FDR-4-8 from Shireen, Inc is a Frequency Multiplier with Input Frequency 1.5 to 4 GHz, Output Frequency 4 to 8 GHz, Input Power 10 to 15 dBm, Conversion Loss 13 to 17 dB, VSWR 2.50:1. Tags: Module with Connectors, Passive, Frequency Doubler. More details for FDR-4-8 can be seen below.