These are black satin tabi socks from Fukusuke, a long-established tabi maker. Of course, they are 100% cotton. Brand new and unopened. The outer fabric uses specially woven, top-quality material that brings out the best in traditional Japanese clothing. These are high-quality tabi socks finished with Fukusuke's unique shape and careful tailoring. These have been stored for a long time in a regular household. Please keep that in mind.