★Germany SCHOTT glass, thickness 1.1±0.05, Planeness 5/2*0.16, transmission: 380-680nm Tmax ≥99%
★Aviation aluminum frame, total thickness:5.8mm, frame net thickness:3.5mm
★Double-faced 36 layer HD nano multi coating with high transmittance and low reflectivity, waterproof, oil proof, scratch resistant
★Diameter from 37mm to 95mm