Thealoz Duo Spectrum Eye Drops Preservative Free for Dry Eyes Thealoz Duo is a preservative-free, phosphate-free and hypotonic solution making it suitable for all Dry Eye patients including those that wear contact lenses. It is presented in the ABAK system providing up to 12 weeks of treatment in a multiuse bottle. The Natural Combination for Optimal: - Preservative phosphate free - Can be used as often as required - Safe to use with contact lens - Economical - contains 300 drops and can be used for up to 3 months from opening - Hypotonic formulation to restore the natural balance of the tears - Hyaluronic Acid provides long-lasting lubrication and hydration - Trehalose protects epithelial cells from dryness and high tear film osmalarity - Easy to squeeze bottle with no wastage - can be used until the very last drop