The MLFD-40540 from Micro Lambda Wireless, Inc. is a Tunable Filter with Tunable Frequency 500 MHz to 4 GHz, Bandwidth 15 MHz, Rejection 50 dB, Insertion Loss 8 dB, Supply Voltage 20 to 30 Vdc( Heater Voltage). Tags: Module with Connectors, YIG Filter. More details for MLFD-40540 can be seen below.