The SA-FMF-1 from Xiamen HDG Telecom Equipments is a RF Surge Protector with Frequency DC to 1 GHz, Insertion Loss 0.15 dB, Operating Temperature -40 to 85 Degree C, Surge Current 20KA(8/20 µs). Tags: Gas Discharge Tube. More details for SA-FMF-1 can be seen below.