Marilyn is a unique barebell kegel exerciser that is a registered trade mark of Dr. Laura Berman. It's made of Resin and stainless steel to add weight. There is some added texture, but it's placement doesn't make much sense. Marilyn's design peaked my curiosity, but I was discouraged by the lack of information provided for instructional use and material guideline. However, this doesn't make Marilyn a bad toy. I found her to be enjoyable and a fun work out.