I have sent them via USPS back to Ogden Utah.They did not fit.I did get a lesson from the woman on the help line on the difference between "nominal size", i.e. what it says on cardboard border of the one that was in the unit, and the "real" size that actually fits in the unit.So live and learn. Not your fault. If that distinction isn't on the website.......A big red boxed warning would save a lot of returns