Clear, spherical, optically worked glass lens. Highly polished for optimum precision. 25mm diameter with 71mm focal length. Ideal for studying optics and properties of light. Clear, spherical, optically worked glass Plano Convex Lens feature one flat side and one convex side. Surfaces are highly polished for optimum precision. Great for optics studies and experiments. Lens diameter: 25mm (1"). Focal length: 71mm.