Stay clean from head to toe. The Jason Markk Hat Care Kit includes an all-new. fragrance-free solution specifically formulated to gently. yet effectively clean hat materials. along with our signature soft-bristled Premium Brush. This gentle new formula is safe to use on cotton. wool. felt. corduroy. polyester and more. Designed for quick and easy care. our Ready-To-Use Hat Cleaner dispenses the perfect ratio of solution to water for the most effective clean every single time.