Product review (4 stars): Specifications for this filter
I found the specifications for this filter: (Amazon deleted my link)  It is basically a charcoal and particle filter.  There is not an NSF stamp on it.  It says it is made to NSF standards, however, it has not been tested by the NSF.  It's filtration must not be as restrictive as the OEM because it will increase your dispenser pressure and you will fill your glass at least twice as fast. It is made in Hong Kong not China as some have speculated.