#4004 Aprilaire In-Line Strainer HF
#4004 Aprilaire In-Line Strainer For use with Aprilaire models 110, 112, 220, 224, 330, 350, 360, 400, 400A, 400M, 440, 445, 445A, 448, 500, 550, 550A, 558, 560, 560A, 568, 600, 600A, 600M, 700, 700A, 700M 760, 760A, 768 and 800. Fits in the inlet fitting of the water solenoid valve which allows water to enter your humidifier or stops the water flow. Designed to keep debris from entering the solenoid valve and should be checked annually for the build-up of minerals and grit. Replace as necessary.