The 250 is the correct replacement for the following humidifier models:
The Autoflo 250 Humidifier Pad Filter replacement is a compatible evaporator pad for the original Autoflo 250 Humidifier Pad Filter. This Autflo 250 is also known as the 40EP. The evaporator pad helps inhibit mineral and slime build up- as well as prevents bacteria, mold, and mildew from getting into your humidifier and humidifier water pad.
Autoflo 250 Humidifier Pad Filter Replacement:
The Autoflo Evaporator Pad replacement helps to ensure that your Autoflo humidifier is releasing the cleanest humidified air into your home. The evaporator pad allows for water distribution inside the humidifier as well as an increased humidity output. The 40EP humidifier water pad fits your Autoflo 40, Autoflo 40S, and Autoflo humidifier model 250. The replacement no longer includes the plastic frame, be sure to keep your old one.