Uses a 13-watt compact fluorescent tube (included) located behind the magnifying lens. The unique placement of the bulb casts light at an angle for highlighting object details. This unique shadowing feature makes details of uneven surfaces pop out to the viewer. This effect is well suited for precise details found in variations of an object’s surface. The three-diopter (75% magnification) five-inch crown optical glass lens has a focal length of 13 inches. Rugged all-metal construction and a durable powder coating allows for years of lasting use. Clamp models will also fit into our bench-friendly bushing mount (13-1823 sold separately). Supplied with 13-watt daylight tube (6500¡K). Tubes/bulbs not covered by five-year warranty.