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
Marina Standing Thermometer - Celsius and Fahrenheit, designed to sink to the bottom of the aquarium and remain in a vertical position, Centigrade, Has a safety zone temperature range indicator for most tropical fi
Convex Mirror, Material: Glass, round, designed for physics and educational uses, Because of their educational use design, there may be minor imperfections that do not affect physical function, thickness varies as they are not designed, Size: 2in Diameter, 300mm FocalLength, 2mm Thick
Convex Mirror, 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, Optically worked, silvered back with protective coating, Size: 1.5in diameter, 100mm Focal Length
Concave Mirror, 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, Optically worked, silvered back with protective coating, Size: 2in diameter, 75mm Focal Length