Roll on & relax. The Happy Head Rollerball was designed with ease of use in mind. Inspired by essential oils to help with headaches such as Peppermint, Lavender, Frankincense and Eucalyptus, we have diluted them in a carrier oil for safe topical application. When you are experiencing a headache or migraine, roll the Happy Head rollerball onto your neck, chest and temples and inhale deeply. Size: 10ml / 0.34fl.oz