This high quality durable optical bench is ideal for classroom experiments dealing with introductory optics. The optical bench is comprised of aluminium and has two meters of measuring tape on both sides of the optical bench which allows for easy reading of the position of the adjustable riders. An NFU with activities is included.Contents are:1.5M Optical Bench x 1Riders x 5Lens Holder with brass holding rod x 4Square Slit Holder x 1Candle Holder x 1White Plastic Screen x 1White Acrylic Screen with 360° Printing (120mm x 120mm)Slit Square - 1 cut x 1Slit Square - 5 cut x 1Slit Square - Arrow x 1Slit Square - 4 Holes x 1Slit Square - Ring x 1Lens - Double Convex Focal Length: 10cm x 1Lens - Double Convex Focal Length: 20cm x 1Lens - Double Convex Focal Length: 30cm x 1Lens - Double Concave Focal Length: 20cm x 1Colour Filter (set of 7 plus 1 x Tricolour)Red & Black Lead (1 Metre) x 1Needle Rod 4"" x 1LED Light Source x 1Extra components (not included):Concave PrismConvex PrismPlane Mirror (50mm x 50mm)