Double Concave Optical round Lens, Material: Glass, designed for physics and educational uses, Because of their educational use design, there may be minor imperfections that do not affect physical function, Size: 150mm focal length, 50mm diameter and 5.5mm thick
Double Convex Lens, Highly polished, optically true lens is excellent for physics classroom demonstrations in optics and light refraction, with ground edges, great for physics classrooms, with highest grade, Size: 100 mm focal length, Lens measures 2in diameter, 0.1 weight
Double Convex round Lens, Material: Glass, designed for physics and educational uses, Because of their educational use design, there may be minor imperfections that do not affect physical function, for educational use, Size: 100mm focal length, 2in diameter and 16.5mm thick