Silicon
Silicone is an artificial polymer used for the production of sex toys for over 20 years. Dolls made of it are very realistic, non-porous, hypoallergenic and heat resistant. Compared to TPE, it is slightly harder and stiffer. Less susceptible to damage, easy to clean and maintain, its only disadvantage is higher price. Detailed information about Silicone Dolls can be found HERE.