This flat convex is applicable to LED spotlights, car lights, focusing flashlights, projection lights, explosion-proof lights, down lights, and other lighting products. Suitable for reading small text in newspapers, books, menus, or labels, these lenses serve as versatile tools for science experiments, DIY telescope projects, or office tasks.Specification:Color: Clear;Material: Borosilicate Glass;Light Transmittance: 92%;Refractive Index: 1.474;Operating Temperature: -50°C to 450°C;Focal Length: 20mm / 0.79 inch;Outer Diameter: 14mm / 0.55 inch;Height: 4.1mm / 0.16 inch;Packing List: 12 x Convex LensAdvantage:Convex lenses are made of borosilicate glass, which is more resistant to high temperatures, has higher strength, and higher light transmittance than other materials, ensuring scratch resistance and long-term use.
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