Opti Free Express is a multi purpose, disinfecting and sterile solution designed to be gentle on the eyes. It contains Polyquad and Aldox which prevent infections. No separate enzyme cleaner or saline solution is required if Opti Free Express is used daily. While your lenses are soaking in Opti-Free Express, the solution conditions the lenses leaving a hydrophilic layer. This maintains a shield of moisture between the lens and eye, improving comfort by relieving dryness and irritation.