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: 250 mm focal length, Lens measures 1.5in diameter, 0.2 weight
Spectrum Discharge Tube, Mercury Gas to show spectral lines of pure substances. Tubes approximately 260mm long, central capillary portion approximately 3-1/2 to 4 (90-100mm) long with electrodes sealed at both ends and connected to lead wires protected by metal caps
Rectangular Block - Glass, Made from imported optical glass with optically worked surfaces, All angles accurately worked with edges slightly bevelled and glass free from bubbles, Size: 125 x 65 x 18 mm