See clearly in the harshest and most critical situations you face today. This prescription lens insert for the Wiley X Nerve goggle is constructed of CR-39, a high-grade optical plastic, proven to avoid distortion when used in combination with the Nerve goggle's polycarbonate lens. Simply present the insert to your local optometrist, have your prescription lenses made to fit and enjoy the comfort and perfect optical clarity of your Nerve Goggle on your next assignment.