The CM-7M design features a seal at the temple that helps secure the rubber outside. Wearing glasses disrupts that mechanism and can cause damage to the mask. I highly recommend wearing contact lenses instead where applicable. MIRA Safety also sells a prescription lens kit that you can insert in place of the default optics on the mask. This helps to simulate the enhanced vision of glasses without damaging the inside of the covering. However, the MIRA CM-7M does accommodate other kinds of external eyewear, including binoculars and night-vision goggles. The dual-lens design allows clear vision into any tools mounted on the outside of your headgear.