This student optical bench kit requires a Hodson Light Box as it's source (not included, can be purchased separately). The 1.2 metre long straight alloy rail is complete with metric scale and carries all the kit parts on plastic mounts. The kit contains mount for the light box, optical targets and scale, white screen, large prism and rotatable table, set of 50mm bi-convex and bi-concave glass lenses of various focal lengths with holders.