The QSSNJNJ0400 from NexTek, LLC. is a RF Surge Protector with Frequency 2.4 to 6 GHz, Input Power 0.5 kW, Insertion Loss 0.1 to 0.15 dB, Operating Temperature -40 to 90 Degree C, Return Loss 20 to 25.7 dB. Tags: Quarter-Wave Shorting Stub (QWS). More details for QSSNJNJ0400 can be seen below.