The 1905A-2 from KR Electronics (A Division of NIC) is a Band Pass Filter with Frequency 15.64 to 18.84 kHz, Bandwidth 3.2 KHz, Center Frequency 17.24 kHz, Insertion Loss 1 dB, Rejection 40 dB. Tags: PCB Mount, Surface Mount, Lumped Component Filter. More details for 1905A-2 can be seen below.