Thanks for the question. The RF221 models feature an internal water dispenser in the fridge compartment while the RF220 does not. The other difference is the finish; the RF220NCTASR and RF221NCTASR both have real stainless steel exterior finishes, while the RF221NCTASP features Samsung's Stainless Platinum finish which resembles real stainless but is fingerprint-resistant and magnetic.
All three of these models measure 29-3/4" wide and feature HE LED lighting, flexible shelving and an automatic icemaker in the freezer.
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