ay hello to Keratin Smooth. TRESemmé Keratin Smooth, with Keratin and Marula oil, gives you 72 hours of frizz control and a 5 smoothing benefits in 1 system. Keratin Smooth hair shampoo and conditioner helps you to achieve hair, that’s smooth,defined and controlled but still full of natural movement. This hair repair conditioner detangles knots, boosts shine, adds softness and tames flyaways.