Think Crucial Universal Humidifier Solenoid Valve, Compare To Aprilaire Part No. 4040, GeneralAire Part No. 990-53, Honeywell Part No. 32001639-002 and Skuttle Part No. A01-0814-148 EXTREMELY DURABLE so when you install your solenoid for your humidifier valve it doesn't break, that way you don't need to replace it for a long time! BETTER WORKING HUMIDIFIER when you fix your solenoid valve! This little guy helps water vapor get into the heated area of your humidifier so that your humidifier can work correctly. Replacing this valve can keep you from needing to buy a new humidifier! EASY TO INSTALL quickly! Plus, if you don't know how to install it, your local appliance repair shop could do it for you, no problem! This valve is comparable to Aprilaire part # 4040, GeneralAire part # 990-53, Honeywell part # 32001639-002, & Skuttle part # A01-0814-148 INCREDIBLY SIMPLE TO USE because humidifiers shouldn't be complicated to use! Having a working solenoid valve can help your humidifier feel like new! GUARANTEED SATISFACTION because of a 30 day full money bank guarantee and a trusted Think Crucial warranty. We are so confident in our products that we have no problem giving you every penny back if you're unhappy with your purchase. You won't see promises like that from big box brands!