The shaft is TENSEI, flex S. I purchased it used. From the time of purchase, there was a mark where some kind of sticker? was attached, as shown in the third photo. Due to the many stains and scratches, please purchase only if you understand. I was using it normally until recently, so I think it can still be used. If you don't mind the appearance, please consider it. Since it's priced low, it will be wrapped in bubble wrap and shipped in paper packaging instead of a cardboard box.