I bought a set of 650 thread count sheets for my bed, but they don't sell extra pillowcases in that thread count so I purchased the 400 TC pillowcases. They actually almost feel softer than the 650 TC sheets, but a word of warning: the colors DO NOT match between the thread counts. It looks like I have Taupe and Mocha pillowcases on my bed when in fact they are all supposedly Taupe.