• Diameter: 34mm (1.34 inches); Thickness: 1.1mm (0.04 inches). • Made with sapphire crystal, resistant and durable, with high transparency and smooth surface. • Resistant to high temperatures, scratches, and deterioration. • Rounded and smooth edges, without scratches, for a pleasant touch. • The light transmission layer in the sapphire glass is white, not blue. • Lens diameter tolerance: ±0.05 mm. Measure with a precision caliper before purchasing. • The indicated size does not include the waterproof ring, which has a diameter of 0.5 mm.