The AmScope SW-3T24-FRL trinocular stereo microscope head has a 2x/4x objective a pair of 10x20mm widefield high-eyepoint eyepieces and a single-arm boom stand. The microscope head has a 3 O-ring style mounting ring. The trinocular viewing head has an interpupillary range of 47 to 75mm a 45-degree inclination to reduce eye and neck strain and 360-degree rotation to enable sharing. The vertical trinocular port can be used as a C-Mount or 23mm photo port (camera sold separately). The WF10x20mm super-widefield high-eyepoint eyepieces combine with the 2x/4x objective to provide 20x and 40x magnification and a longer working distance for inspecting large-scale specimens that require handling or repair. High-eyepoint eyepieces ease viewing for users who wear glasses dioptric adjustment accommodates individual eye-strength differences and eye guards ensure comfortable viewing. The optical glass lenses provide sharp images and are fully-coated to ensure high-resolution images. 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 removable 8W fluorescent ring light provides cool white light for observing specimens as they would appear in their natural environment. A ring light provides shadow-free illumination. It has a 2-3/8 inner diameter and uses a 110V power supply. The microscope has a 17 pillar that has an 8 vertical working distance. The 16 single-arm boom has a 24 overall length. Bilateral focus eases use for left- and right-handed users. The microscope head can be rotated on the X- and Y-axis. The solid cast-steel base is 1-3/4 x 9 x 9 inches (H x W x D where H is height the vertical distance from the lowest to highest point; W is width the horizontal distance from left to right; D is depth the horizontal distance from front to back). SpecificationsHeadTrinocularMagnification20x 40xObjective power 2x/4xEyepieces (30mm)WH10x20mmTrinocular portC-Mount or 23mmOptical working distanceUp to 4 Field of view0.787 at 10xMicroscope standSingle-arm boom standHead movementX- and Y-axesIllumination typeEpiscopic (reflected)Light sourceFluorescent ring 8WPower110V-120V 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? Trinocular stereo zoom head with 2x/4x objective WH10x eyepieces one pair Single-arm boom stand with focus rack Fluorescent ring light 8W (FRL8) Eye guards one pair