The IS-75F-C1 from PolyPhaser is a RF Surge Protector with Frequency 4 to 900 MHz, Input Power 100 W, Insertion Loss 0.2 dB, Operating Temperature -45 to 50 Degree C, Storage Temperature -45 to 85 Degree C. Tags: Gas Discharge Tube. More details for IS-75F-C1 can be seen below.