The 100025539 from Telegartner is a RF Surge Protector with Frequency DC to 3.8 GHz, Insertion Loss 0.1 to 0.25 dB, Operating Temperature -40 to 85 Degree C, Return Loss 20 to 30 dB, Surge Current 2.5 to 15 kA. Tags: Gas Discharge Tube. More details for 100025539 can be seen below.