2-in-1 Spring-Arm Magnifier Desk Lamp - Large 7-1/2" X 6-1/4" Lens - 5 Diopter Professional quality UL listed lamp provides efficient daylight-spectrum fluorescent light Large 7-1/2 x 6-1/4" optical-quality precision ground lens shows fine detail with excellent clarity 5-diopter magnification enlarges print, text and work pieces to 225% actual size; lens dust cover Automatic memory arm adjusts position with finger touch and then holds it; 3-way swivel lamp head Anti-tip base without clamps or attachment; UL-listed lamp with convenient lamp-head power switch