Diopter: 6Magnification (w/ 3.5-Diopter Lens): 3.38xWorking Distance (W/ 3.5-Diopter Lens): 4.3"Magnification (w/ 5-Diopter Lens): 3.75xWorking Distance (w/ 5-Diopter Lens): 3.5" Lens Diameter: 2"Lens Diameter (Overall w/ Gasket): 2.5"