Two 38 mm spherical lenses; one is a double concave, the other a double convex, each with a focal length of 150mm. When placed together the net focal length is zero. (1-1/2" x 1-1/2" x 1/4"; .005Ib).
Great for optics experiments in the lab or classroom.
Use this awesome prism to teach about optics and light in the classroom setting!
Create beautiful art with this amazing sun paper!
The Star-Ball Magnetic Puzzle is the perfect creativity tool for innovators, artists, writers, students, and you!
This microscope is so versatile you can even take it with you on a job site!
This high precision gyroscope will amaze you with rotational speed and ease of precision.
This magic bird defies gravity before your very eyes!