The FMSP1028 from Fairview Microwave is a RF Surge Protector with Frequency 125 MHz to 1 GHz, Input Power 50 to 375 W, Insertion Loss 0.1 dB, Operating Temperature -50 to 50 Degree C, Return Loss 26 dB. Tags: Gas Discharge Tube. More details for FMSP1028 can be seen below.