Each roller contains high quality essential oils that have been blended specifically to correspond with each chakra and crystal. These oils can be applied to your temples, wrist, chest and/or neck. As with all essential oil products, plese avoid contact with sensitive areas of skin such as eyes, nose, mouth, etc. Consult a physician prior to use if you have any health concerns. Although essential oils provide excellent health benefits, some oils are not good for children under 16 years of age.