Popular Primary Schools Resource! BEST SELLER!
 
Throws a spectrum up to 78-3/4 in. (2 m) long! Made from 1/4 in. acrylic, this 16 in. H right angle prism will withstand the abuse of the classroom. When filled with water, mineral oil, or another fluid, it will display a huge, brilliant spectrum the whole class can see. Prism was constructed utilizing the same techniques used for building aquariums and will not leak under normal use, rot, rust, warp, or become opaque. 
Integrated lid contains a hole for filling the unit. 
Works best with sunlight or a bright laboratory lamp. 
Includes instructions.