Salonpas Ultra Thin Patch contains Methyl salicylate 10 % and i-menthol, which work by causing the skin to feel cool and then warm. These feelings on the skin distract you from feeling the aches/pains deeper in your muscles, joints, and tendons. These patches can be used for relief of aches, pain and inflammation associated with muscle fatigue, muscle pain, stiff shoulder, simple backache, bruises, sprains, strains, arthritis, bone fracture and minor frostbite.