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

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

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!

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 set to learn about lenses.

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 .

all three convex lens scratched at center

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.

I read reviews for other products and they didn’t have labels and I don’t know how you would tell. I wrote directly on them with a sharpie on the edge I put “1” and then on the little sleeve I put “1” on the corresponding little envelope it came in so they couldn’t get mixed up.