Acrylic Prisms, Boxed set of 7

Consists of 7 blocks, all faces fully polished, 25mm thick. Rectangle: 75 x 50mm. Semi-circular: 75mm dia. Triangle: 60 x 60 x 60 degrees with 58mm side. Triangle: 90 x 45 x 45 degrees with 75mm hypotenuse. Triangle: 90 x 60 x 30 degrees with 75mm hypotenuse. Bi-convex: 75mm long curved faces, 100mm radius. Bi-concave: 75mm long curved faces, 100mm radius.