The RCF-1681.000-2017000-1608-W-001 from Raltron is a Low Pass RF Filter with Frequency 673 to 2690 MHz, Bandwidth 2017 MHz, Stopband Frequency 4950 to 12500 MHz, Insertion Loss 0.42 to 0.5 dB, Rejection 27 to 35 dB. Tags: Surface Mount, Ceramic Filter. More details for RCF-1681.000-2017000-1608-W-001 can be seen below.