EISCO 6pc Optical Lens Set, 2" (50mm) Diameter - 3 Double Convex Lens & 3 Double Concave Lens - 200mm, 300mm, 500mm Focal Lengths - Optically True Glass - Ground, Beveled Edges

I was excited about receiving the lenses . The lenses are high quality and I would recommend this to anyone . To microscopic to telephoto lens . It'll keep me busy . You can't find the selection when you come to a store . They are useful , since I am going to build a telephoto lens for my camera . And they are inexpensive also . I saw the same lenses at other sites twice the price . I am really satisfied with this purchase .

I bought these lenses for a science lesson on optics. They were perfect. I was able to use two of them to make a simple telescope using a cardboard tube. The students were completely fascinated by their shape.

Nice quality, no chromatic aberration. The size enables a good wide field of view when a lens is held close to the eye. The 20mm lens is my preference for checking small print or objects. A student could build a low-power telescope with a pair of these lenses.

Nice set to learn about lenses.

The lenses arrived in record time and are exactly what i need for my basic telescope project. Highly recommend these lenses. Thank you!

Didn't have much curvature, I used them in home made kaleidoscopes and they didn't magnify much at all.

One of my students had been having trouble with eyesight for months. She looked through the correct lenses and was amazed that the board was now visible and could be read!

Purchased these after my son and I had a discussion about how glass bottles acting like lenses can start forest fires. The lenses are clear and high quality. Each comes in a separate paper envelope clearly marked with focal length and diameter. I had no issues with this purchase and I am happy with the product.