RK By Kiss Charcoal Peel Off Mask. Apply a thick, even layer to clean, dry skin. Avoid eyebrows, hairlines, and lips. Leave on for 20-25 minutes or until completely dry. Gently peel off mask from outer edges. Rinse throughly with warm water followed by RK charcoal cleansing foam for best results. Follow with moisturizer. Use 1-3 times a week as needed.