The AmScope SE306R-AZ stereo microscope has interchangeable pairs of 10x18mm and 20x10mm widefield eyepieces 2x and 4x objectives upper and lower halogen lighting two stage plates and an arm stand. The forward-mounted binocular viewing head has an interpupillary range of 55 to 75mm and a 45-degree inclination to ease viewing for young users. The WF10x18mm and WF20x10mm eyepieces combine with the 2x and 4x objectives to provide 20x 40x and 80x magnification and a longer working distance for inspecting large-scale specimens that require handling or repair. The optical glass lenses provide sharp images and are fully coated to ensure high-resolution images. Dioptric adjustment accommodates individual eye-strength differences and eye guards ensure comfortable viewing. 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 microscope has upper (episcopic) illumination that reflects light off the specimen for enhanced visibility of opaque specimens and lower (diascopic) illumination that transmits light up through the specimen for enhanced visibility of translucent and transparent objects. The 10W halogen light source provides bright light in a concentrated path. Bilateral coarse focus eases use for left- and right-handed users. The stage has a frosted stage plate for use with lower (transmitted) lighting and a reversible black and white stage plate that provides contrast with light- and dark-colored specimens when used with upper (reflected) lighting. Stage clips that secure the specimen during viewing. The microscope has a 2-1/8 (53mm) working distance. All metal construction is durable and stain-resistant. SpecificationsHeadForward-mounted binocularMagnification20x 40x 80xObjective power 2x 4xEyepieces (DIN 30.5mm)WF10x18mm WF20x10mmWorking distance2-1/8 (53mm)FocusBilateral coarseMicroscope standArm standStage plate (95mm)Frosted and reversible black/whiteIllumination typeUpper (reflected) and lower (transmitted)Light sourceHalogen 10WPower120V UL listed Microscopes 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 SE306R-AZ stereo microscope with forward head and arm stand WF10x18mm eyepieces 30.5mm one pair WF20x10mm eyepieces 30.5mm one pair 2x objective 4x objective Black/white stage plate 95mm Frosted stage plate 95mm (2) Eye guards (2) Stage clips Halogen bulb Dust cover Power cord Instructions