4head quickstrip cooling strips are advanced gel patches that work by helping to relax tense head and neck muscles and can provide up to 6 hours of pain relief they are fast working which means you can use one as soon as headache or migraine strikes for instant relief these strips are contain levomenthol which is 100 natural and can help to soothe and leave a cooling and tingly sensation this product does not leave any visible residue and can be cut to size for easy and convenient usage