Silicone-based elf primer is a type of face primer that is formulated with silicone as its main ingredient. Silicone is known for its ability to create a smooth and even base for makeup application, while also providing a protective barrier between the skin and makeup. Elf's silicone-based primer, called the "Hydrating Face Primer with SPF 15," is designed to smooth out fine lines, blur imperfections, and create a soft, dewy finish. It is also infused with vitamin E and aloe vera to help keep the skin hydrated and moisturized.