Punti Di Vista Keratin Liss Care Straightening System 1 LitreKeratin Liss Care Straightening System1L Windplex Reinforce N1 is a liquid sulfur bridge multiplier used as an additive in your color or bleaching mixture. It acts deeply and structurally, thanks to its exclusive chemistry, multiplying the material that is broken down during chemical treatments or mechanical stress. You can apply it to protect your hair during or after stressful treatments (e. g., keratin treatments, perms, straightening) or to