BIOTOP 19 Pro Silver Serum is a professional-grade treatment designed for cool blonde, silver, white, and gray hair. This lightweight, purple-tinted oil-serum neutralizes yellow and brassy tones while deeply hydrating and smoothing each strand. Its advanced anti-yellow technology controls frizz, enhances shine, and maintains color vibrancy without leaving any greasy residue. Instantly absorbed, it leaves hair soft, silky, and luminous, preserving the natural beauty of your cool-toned hair with every use.