Provide the benefits of traditional Chinese fire cupping with these thick, heavy-walled glass cups. Create vacuum with the heat from a burning, alcohol-dowsed cotton ball, candle, or disposable lighter that is removed from the cup before application. These cups feature a flat top for safely resting after cleaning and are available in the following diameters: 1.5" (small), 1.9" (medium), 2.2" (large), and 2.5" (extra large). The set contains one cup each of the small, medium, and large sizes.Note: Autoclaving not recommended for these cups.