Product review (5 stars): Looks at fits like the Original
Looks at fits like the Original.  My frig is a Thermador 48" refrigerator using the Whirlpool designed water filtration system (old Whirlpool part #4396510).  Was worried that the neck was a little shorter than the original but if you look closely the body of the filter it now has grooves in it that help the threads.  Fit like a glove into my frig with no issues. Actually easier than I remembered it in the past with the original.  Also, my water flow was dramatically increased which is great as it takes shorter time to fill your pitchers.  And I like the fact that this filters more things out than the original (as stated on packaging and website).