1. The lens adopts high-definition achromatic design, suitable for scientific instruments such as DIY binoculars, observation mirror and viewfinder2. Note: In the assembly direction, the thin side of the lens faces the direction of the scene, while the thick lens faces the direction of the lens barrel3. Composition: It is composed of two independent lenses, with achromatic function4. Features: Sturdy and reliable, easy to use5. Anti-reflection lens is coated with anti-reflection film, which has less reflection and good permeability.7. You can purchase and choose different shipping methods according to your needs8. If you have any questions, you can contact us