The Fenwicks Superior Black Streak Remover is a ready to use formula .It has no caustics, abrasives, solvents or silicon’s. It will remover black streaks and other stubborn marks of f your caravan or motor home. Simply spray on and leave to soak for 1 to 2 minutes and then rub off with a sponge or cloth, then rinse with water.By using this product you will get a showroom finish every time .