This 42-inch optical bench is constructed with a square-section aluminum tube and features 1cm graduations along a 100cm rail. It is supplied with four riders for lens and slit holders, along with a 12V LED light source with a United States 110V plug. The kit includes one double concave lens, one double convex lens, one plano-convex lens, and one plano-concave lens. The bench can be used to measure the focal length of lenses and is well suited for physics experiments and optical investigations.