Active bandpass filter with 4 times amplification. It has a high-pass 3-pole butterworth circuit (-3 dB at 1 Hz, -30 dB at 0.3 Hz), and a low-pass 3-pole butterworth cirtuit (-3 dB at 20 Hz, -30 dB at 50 Hz).
References
Scherz P, Monk S (2016) Practical Electronics for Inventors, 4th edn. Edition: McGraw-Hill Education TAB.