4004 Humidifier Drain Type in-Line Strainer Red (2 Pcs) and Humidifier Parts Yellow Orifice 4231 (2 Pcs) Compatible with Aprilaire Humidifier 400, 500, 550, 550A, 558, 560, 560A, 568 and 600

4079 Humidifier Feed Tube Assembly Kit with Nozzle, Sleeve Nut, Orifice, Strainer for 500 Series Compatible with Humidifier 110, 220, 500, 500A, 500M, 550, 550A, 558

4235 Feed Tube Nozzle Assembly with Sleeve Nut Compatible with Aprilaire 700 Series Aprilaire Humidifier Models 700, 700A, 700M, 760, 760A, 768

4331 Humidifier Water Distribution Tray Replacement (1 Pcs) Compatible with Aprilaire Humidifier Models 600,600A,600M

4335 Feed Tube with Sleeve Compatible with 600 Aprilaire Humidifiers 400, 500, 600A,Includes Yellow Orifice (4231), in-line Strainer (4004)

4750 Humidifier Maintenance Kit, No. 35 Water Panel Model Replacement Filter for AprilAire Humidifiers 700, 700A, 700M, 760, 760A, 768

4839 Humidifier Maintenance Kit with No. 35 Water Panel Model Humidifier Filter, Replacement Parts for Models 600, 600A and 600M

H510EZ1A 4793 Humidifier Filter/Water Panel Assembly Replacement Kit Compatible with AprilAire Whole-House Humidifier Models: 500, 500A, 500M, 550, 580