In the words of Old Blood Noise Endeavors:

BL-37 is a reverb pedal within our BL line. It features modulation at two points in the reverb trail to give a wandering, lush reverb unlike any of our other reverbs, with a simplified control set. The Clock slider is the key to its magic, moving from a quick, tile-bathroom echo out to a dark, lofi-stretched reverb, unlike any space in existence.