Boston Conditioning Solution Advance Comfort is a maintenance liquid for rigid gas permeable contact lenses with strong disinfecting action. The product is intended for use with rigid gas permeable, semi-rigid, and scleral lenses. It is not suitable for soft contact lenses.It is the second step for the maintenance (wetting, soaking, disinfection) of your lenses at night and for their hydration before and during their use. The dual disinfection system provides excellent protection from harmful microorganisms and includes a patented moisture layer formation system that soothes your eyes.