Reddit reviews 6pc Optical Lens Set, 2" - 200mm, 300mm, 500mm Focal Lengths - 3 Double Convex & 3 Double Concave, 2" (50mm) Diameter Lenses - Optically True Glass - Ground, Beveled Edges - Eisco Labs
We found 3 Reddit comments about 6pc Optical Lens Set, 2" - 200mm, 300mm, 500mm Focal Lengths - 3 Double Convex & 3 Double Concave, 2" (50mm) Diameter Lenses - Optically True Glass - Ground, Beveled Edges - Eisco Labs. Here are the top ones, ranked by their Reddit score.
SPHERICAL || Each lens is spherical in shape and measures 2" (50mm) in diameterFOCAL LENGTH VARIETY || Converging and diverging focal lengths in 200mm, 300mm and 500mmOPTICALLY WORKED GLASS || Made of high quality, optically worked glass. Highly polished with ground edgesGREAT FOR PHYSICS CLASSROOMS || This optically true lens set is excellent for physics classroom demonstrations in optics and light refraction
Ok man... here we go I got a plan for you. You should build a time machine and you could go into the future and spend that $50 on some trees when they were available...
The Plan
You need
The Time Machine
Take the money you have NOW for the trees and place it in an envelope, and put the envelope somewhere safe. You will be taking this envelope into the future with you. Now, take all the other stuff and go build a time machine.
One of the two things will happen
The way I see it, its a win win.
At the time when I was first ordering, the link that Google provided was sold out so I searched amazon for an alternative. I don't know anything about lenses though, and I didn't realize double convex and bi-convex were not the same thing.. so I ended up with these: http://www.amazon.com/gp/aw/d/B00BIKGMZ8 . In addition to not being the correct style of lens, they're also too big (50mm diameter instead of the 25mm they are supposed to be. )
https://smile.amazon.com/gp/aw/d/B00BIKGMZ8/ref=mp_s_a_1_9?ie=UTF8&qid=1501301361&sr=8-9&pi=AC_UL420_SR280,420_FMwebp_QL65&keywords=lenses
Looks like they're designed for classrooms. There are other packs about the same price with different selections.