The AmScope SE420Z professional stereo microscope has interchangeable pairs of 10x and 20x widefield eyepieces, a 2x objective, tungsten lighting, and a boom-arm stand. The binocular viewing head has an interpupillary range of 50 to 77mm and a 45-degree inclination to reduce eye and neck strain. The interchangeable pairs of WF10x18mm and WF20x10mm eyepieces combine with the 2x objective to provide 20x and 40x magnification, and a longer working distance for inspecting large-scale specimens that require handling or repair. Dioptric adjustment accommodates individual eye-strength differences. A stereo microscope, sometimes called an inspection or dissection microscope, has low magnification and a long working distance that enables users to manipulate the object being inspected. The 10W tungsten light provides bright light, and is side-mounted on the microscope head to adjust simultaneously when the head is moved. The microscope has a 13.5" pillar that provides a 6" vertical working distance. Bilateral focus eases use for left- and right-handed users. The 17" boom arm has a 12" working distance. The microscope head can be rotated on the X- and Y-axes. All metal construction is durable and stain-resistant. SpecificationsHeadBinocularMagnification20x, 40xObjective power1xEyepieces (DIN, 30.5mm)WF10x18mm, WF20x10mmFocusBilateral coarseMicroscope standBoom-arm standVertical working distance6" (13.5" overall pillar length)Boom arm12" working distance (17" overall length)Head rotationX- and Y-axesIllumination typeUpper, reflectedLight source10W tungsten, side-mountedPower110V-120V, UL listedMicroscopes are instruments used to enhance the resolution of an object or image. Types include compound, stereo, or digital. Compound microscopes use a compound optical system with an objective lens and an eyepiece. Stereo microscopes show object depth in a three-dimensional image. Digital microscopes are used to display an image on a monitor, rather than looking through a lens. Microscopes can have monocular (one), binocular (two), or trinocular (three) eyepieces, with varying magnification abilities. Magnification ability refers to the size of an image. Resolution, also known as resolvant power, refers to the clarity of the image. The interaction between field of view (FOV), numerical aperture (NA), and working distance (WD) determines resolution. Microscopes can control magnification through a fixed focus, or through a range of adjustments. They can also utilize LED, fluorescent, and mirror light sources to help control viewing capabilities. Microscopes are widely used in education, lab research, biology, metallurgy, engineering, chemistry, manufacturing, and in the medical, forensic science, and veterinary industries.United Scope manufactures microscopy equipment and accessories under the brand name AmScope. The company, founded in 1996, is headquartered in Irvine, CA.What's in the Box?AmScope SE420Z stereo microscope with boom-arm standWF10x18mm eyepieces, 30.5mm, one pairWF20x10mm eyepieces, 30.5mm, one pair2x objective(2) Eye guardsTungsten lightDust coverPower cordInstructions