Brand New! A Deeply Conditioning Hair Mask To Rejuvenate The Hair & Scalp Based on an 1860 Bristo Place recipe. Our founder Duncan Napier would make a hot water extract of rosemary for his famous hair tonics. Herbstrong Conditioning Mask combines rosemary extract with 12 other powerful herbs selected specifically to support healthy hair and scalp. This natural conditioner helps to reduce tangles, increase strength and delivers marvellous shine. The formula is free from artificial fragrance, parabens, sulphates and phthalates.