The Fresnel Diameter Acrylic Education Concentrator is a great investment for anyone interested in optics .Its design is perfect for science education. It can transform any plane wave into a spherical wave with adjustable concentric rings. The pros of this product include its affordability, ease of use, and durability. One potential con is that it may not be suitable for industrial and scientific use. Overall this concentric ring lens is an excellent choice for educational settings..