Lens and prism set.
Devin from USA, Sacramento, CA
I was looking for the lowest price on a glass prism set. They were well cut and worked for all my experiments but a number of them arived chipped. They were wrapped in tissue to keep them clean but there was nothing separating them to keep them from breaking. Okay for laser pointers but if you are using anything with more power spend more and get a set that is packaged better.