The Original: Pixie Tip™ fits snugly on your favorite reusable straw so that you no longer need to purse your lips while drinking. This anti-purse mouthpiece is designed to follow the natural curvature of your lips making it easier to drink from a straw than you ever thought possible! Not to mention that repetitive pursing of the lips has been linked to mouth wrinkles over time. The unique bow design combines functionality and style for for an enhanced drinking experience unlike any other.   SIZES: Small: For straws 6mm to 8mm in diameter Large: For straws 8mm to 10mm in diameter (For straws 8mm in diameter, we recommend the large)