The "Prescription lens compatible" parameter indicates that the smart glasses are designed to be fully usable by people who require corrective lenses for clear vision. The most common solution is the use of a special prescription insert, which is either included in the package or can be purchased separately. The user takes this insert to their optician, who produces and fits custom prescription lenses into it based on a prescription. The user then simply attaches the finished insert with lenses into the inner part of the smart glasses themselves. This ensures that they see both the image projected by the glasses and the real-world surroundings clearly. Some models may also be designed to be worn over existing conventional prescription glasses.