American Educational 7 Piece Glass Lens and Prism Set

Amazon.com Price: $30.30 (as of 03/01/2020 03:13 PST- Details)

Set of seven lenses and prisms for demonstrating optical principles and effects for students
Includes double-concave, double-convex, trapezoidal, plano-convex, and various triangular shaped lenses
One surface of each lens is frosted to help reveal the path of a light