I think Fresenius brand is the best out there…probably the OptiFlux model…I’ve tried both the F80, F8, F7NR, F70NR, and OptiFlux and found that OptiFlux gave me minor reactions. The F70NR would give me a very bad headache…
I do believe there are other alternatives but Fresenius is the BIG BOY…cadillac of all dialyzer…in my opinion… 
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