Product review (5 stars): Fix for defrost drain ice dam backups.
This fixed my problem of condensation in my refrigerator after I trimmed the original defrost nipple drain. The original rubber drain had a small slit opening that would plug and the defrost water would back up and make an ice lake in the bottom of the freezer. A You Tube video showed trimming the end of the nipple off to allow better draining. It worked, but the bigger opening allowed hot air from the evaporator drain pan area to enter the refrigerator and cause condensation to build up inside. This p-trap drain solved both problems. Big drain opening and the p-trap full of water prevents hot air from entering the fridge. Simply fix. Just be sure and use hot water squirted through a turkey baster to melt the original defrost ice drain clog.