The Sheath Safety Glass is designed to fit over most prescription glasses. Close fitting design with adjustable temples. One piece lens design for safety and comfort. Telescoping Temples for a customized and comfortable fit. Ratcheting temples provide lens angle adjustment. Polycarbonate lens provides impact resistance with a single protective lens design.Provides 99.9% UVA/UVB protection.Meets or exceeds ANSI Z87.1 + standards.