Product review (5 stars): I used these on my old fridge that had no ...
I used these on my old fridge that had no internal water filter.  When I got a new fridge with an internal filter, I had sticker shock when it came time to replace it.  I still use these inline filters WITH the internal filter.  I replace the inline filter at it's regular interval, but since it's before the internal filter, I can go 4x longer.