The "Classic" Tee is 9R's version of what a good t-shirt should be. It is soft, has some stretch, good length, is slightly fitted so that it's not "boxy." The fabric spin allows this shirt to be lightweight. The kind of t-shirt a person would like to live in.
The "Heather" color choices contain a blend of polyester. These shirts are slightly lighter weight and have an even softer feel.