Always use the Edge microfiber cleaning bag. This eliminates the opportunity for scratches, damage to the coatings like Vapor Shield, and will prolong the life of the glass. Store the glass in the cleaning bag when not being used to maximize the life span of the glass and to prevent possible further damage. Never use chemicals to clean these glasses as this can prematurely damage coatings as well. Normal wear and tear as well as sweat will eventually break down the coatings after time. That time is different from each person and their acidity levels and/or the caustic environments they work in. Water can be used to help clean lenses but once again, depending on the chemicals found in the water, eventually it could breakdown the coatings prematurely. Never use anti-fog spray on a glass using Vapor Shield coating. This will cause damage to the glass as they are 2 distinct types of anti-fog systems and are applied differently. When using a lens wipe, this can potentially reduce the life span of coating.