Prism and Lens Sets These superior quality yet economical prisms and lenses can be used to teach a wide variety of optical principles. Set includes: double convex lens, double concave lens (can be used together with double convex lens), semicircular lens, trapezoidal prism, small right angle prism, equilateral prism, large right angle refraction prism. This set is housed in a wooden case. Shipping weight 2 lbs., dimensions 9.25 x 8 x 2. Prisms and Lens Set of 7-Glass Qty :