100% natural boar bristles are best suited for fine hair, they are gentle on the scalp and hair shaft. Renowned for their strength and resilience, good quality boar bristles have a natural stiffness, but give as they are drawn through the hair. They maintain good hair condition by keeping it clean, stimulating the scalp and distributing oils for a healthy, glossy look.  Hair on hair is actually very beneficial and encourages natural shine and health.