Silica gel: Also known as silica gel, also known as silicone rubber, it is a highly active adsorption material and is an amorphous substance. It is insoluble in water and any solvent, non-toxic and tasteless, chemically stable, does not react with any substances except strong alkali and hydrofluoric acid, and has high mechanical strength and flexibility. Silicone dolls feel harder than tpe, but they have high quality, high simulation, and no oil. It is the best material for making adult dolls.