Redken Intra-Force System 1 Shampoo for Natural Hair 290ml This Intra-Force System 1 Shampoo works to promote thicker fuller hair within 30 days of use. Providing a deep yet gentle cleanse this nourishing shampoo is specially formulated with Zinc PCA Argininr & Vitamin E which combine to give you super soft voluptuous locks with up to 95% less breakages.