The S3906 from Mercury Systems is a Low Pass RF Filter with Frequency 1900 to 3050 MHz, Stopband Frequency 3800 to 10000 MHz, Insertion Loss 0.25 dB, Rejection 55 dB, Upper Rejection 55 dB @3800 to 10000 MHz. Tags: Module with Connector. More details for S3906 can be seen below.