Boston Advance Comfort Formula System is the #1 doctor recommended two-bottle lens care system for GP (gas permeable) lenses. It provides overall superior performance and comfort. Boston Advance Cleaner and Boston Advance Comfort Formula Conditioning Solution are easy to use. Boston Advance Comfort Formula Conditioning Solution Boston Advance Comfort Formula Conditioning Solution provides exceptional lens wearing comfort by coating the lens. Its patented dual preservative system provides excellent disinfection to destroy harmful microorganisms on your lenses.