Crystal, stone, which eliminates the unpleasant smell of sweat. Design (dark color) is designed specifically for men. Bottom twisting, it extends. It must be very good care, so as not to break. I'm more of a roller or in a spray version. According to the properties they are all the same. If my review was useful for you, please click the bottom of the "YES", and go to my profile, by clicking at the top of GreenLight blue and read my reviews of other products purchased by me at iHerb. Thank you very much.