Systane Ultra UD is a preservative-free lubricant eye drop solution that comes in 30 single-use vials. It contains Polyethylene Glycol 400 0.4% and Propylene Glycol 0.3% to provide temporary relief from eye dryness, irritation and burning sensations. Each single-use vial should be discarded after one use. The drops can be used as needed throughout the day and are safe for contact lens wearers. Store at room temperature and keep away from direct light. If eye irritation persists for more than 72 hours or if you experience changes in vision, discontinue use and consult a healthcare professional. Keep out of reach of children.