#4231 Aprilaire Yellow Orifice

For use with Aprilaire models 400, 500, 550, 550A, 558, 560, 560A, 568 & 600.

These are the tiny nylon components which, accurately meter the flow of water into your humidifier.

Allows a specific amount of water to go into the humidifier, some of which is evaporated and some which performs the important flushing action.

Keeps the Water Panel clean and reduces maintenance to a minimal amount.