classic style, uncompromising performance. the dragon d1 otg comes with a slightly larger fit, making it easy to wear over prescription glasses. in addition, this design offers another peripheral field of view. combined with premium features like lumalens® lenses and a super anti-fog coating, the d1 otg offers maximum comfort and a clear view, no matter what conditions you're on the mountain.lumalens® flash blue lumalens® technology provides optimised colour and glare protection through an ionised lens coating. the hard coating is scratch resistant and repels dirt, dust, oil and water.transmittance of visible light: 51 %lumalens® dark smokelumalens® technology provides optimised colour and glare protection through an ionised lens coating. the hard coating is scratch resistant and repels dirt, dust, oil and water.transmittance of visible light: 23 %