Synthetic brush is perfect for any scrubbing and cleaning, removes any dirt and loose material from your suede/nubuck shoes. Brushing your nubuck/suède shoes with a synthetic brush will also restore the natural looks without creating marks or scratches in the leather. Especially nubuck can be sensitive to this. So try to avoid using a brass brush if you can during regular maintenance on your suede and nubuck shoes and instead go for one of the synthetic brushes available on Loafers's website.