The 2356 from KR Electronics (A Division of NIC) is a Band Pass Filter with Frequency 0.02 to 0.42 kHz, Bandwidth 400 Hz, Center Frequency 0.22 kHz, Insertion Loss 3 dB, Rejection 30 dB. Tags: PCB Mount, Surface Mount, Lumped Component Filter. More details for 2356 can be seen below.