Product review (2 stars): Filter replacement and building arks
These would have been great had they actually been the replacement for the filter model I needed for my Kenmore refrigerator as reported.

Don't get me wrong.  I think at one time they may have been based on size and circumference but I discovered - in a deluge of spewing icy cold refrigerator water - that they are not now.  At the neck of these filters is a small piece of plastic that is rectangular in shape and sticks out from the neck to help "lock" the filter in place.

Well, in inadvertently recreating an upside down geyser in my refrigerator, I discovered that the rectangular pieces on these new filter necks are different from the rectangular pieces on the Kenmore brand filter - the Kenmore "rectangle" was missing the top left and bottom right corners.  It turns out those corners are incredibly helpful and necessary in keeping the filter attached to the refrigerator the moment water begins circulating through...

...or you will be drying out the inside of your refrigerator and any items that were in the flood zone...and if you are like me, before figuring out what was going on, you'll be doing this twice.