The CFMU501X420 from Cernex Inc is a Frequency Multiplier with Input Frequency 500 MHz to 1 GHz, Output Frequency 2 to 4 GHz, Output Power 20 dBm, Harmonics 7 dBc, VSWR 2.00:1. Tags: Module with Connectors, Active, Passive. More details for CFMU501X420 can be seen below.