Matrix SoColor 90mL 4RB SOCOLOR.beauty contains pre-adjusted tones and bases to compensate for natural underlying pigments and patented Cera-Oil complex, which restores condition, delivering long lasting colour and brilliant shine. A comprehensive palette of beautiful shades to give natural or fashion effects. ABOUT Matrix Matrix was founded in 1980 by the American husband and wife hairdressing team, Arnie and Sydell Miller. Matrix is the no. 1 American professional brand in the world empowers hairdressers all around the world with accessible innovation and education that are on the cutting edge. With innovative and smart products, Matrix allows hairdressers all over the world to share the American dream and imagine all they can be! Blending nature with science, deliver natural, healthy-looking hair for every need and hair type. Matrix offers all the support hairdressers need: from affordably-priced products that really work to localized grass-roots education and complete in-salon marketing. The brand truly understands what it means to be a salon professional. Please note: This product must be mixed with a developer or peroxide before applying to the hair (sold separately).