AFFORDABLE PRODUCTS-Halogen magnifier swing arm lamp mounts to most table surfaces. Also adaptable to most needlework frames (screw clamp is easily removed to expose a pin which fits into the back of most floor frames). Swing arm measures 36" when extended. The lens is a 3 diopter lens with 130mm diameter. An interesting feature of this lamp is that the magnifier lens and the halogen light swivel so that light and magnification are controlled separately and if desired one without the other. 20 watt halogen bulb included.