The ManCave Caffeine Shampoo is designed specially for the needs of men. Understanding the importance of virility, the natural formulae gel helps to encourage hair stimulation whilst cleansing and revitalising the hair and scalp leaving roots stronger. The ManCave Caffeine Shampoo is designed specially for the needs of men. Understanding the importance of virility, the natural formulae gel helps to encourage hair stimulation whilst cleansing and revitalising the hair and scalp leaving roots stronger.