The AmScope SM-1BSZ-144S professional stereo zoom microscope has a pair of 10x super-widefield high eyepoint eyepieces, a 0.7x-4.5x zoom objective, two Barlow lenses, and a pillar stand. The microscope has an overall magnification range of 3.5x-90x. The binocular viewing head has an interpupillary range of 55 to 75mm, a 45-degree inclination to reduce eye and neck strain, and 360-degree rotation to enable sharing. The WH10x20mm super-widefield high-eyepoint eyepieces combine with the 0.7x-4.5x zoom objective to provide 7x-45x continuous zoom magnification and a longer working distance for inspecting large-scale specimens that require handling or repair. High-eyepoint objectives ease viewing for users who wear glasses, and dioptric adjustment accommodates individual eye-strength differences. The microscope includes 0.5x and 2.0x Barlow lenses that can be added to the objective to increase the magnification range. A Barlow lens with a magnification of less than 1.0 reduces magnification and increases the working distance, while a Barlow lens with a magnification greater than 1.0 increases the magnification and reduces the working distance. 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 144-bulb LED ring light provides bright, cool light for working with temperature-sensitive or live specimens. The ring light provides shadow-free illumination, and a rheostat controls the amount of light emanating from the lamp. Power and adjustment controls are located on the light head. The ring has a 2.4 (61mm) inside diameter and a 4 (100mm) outside diameter. It has a 100,000-hour life span and a 110V-240V variable power supply. The table stand has a reversible black and white stage plate that provides contrast with light- and dark-colored specimens, and stage clips to secure the specimen in place. The stage plate has a 3-3/4 diameter (95mm). The stand is 10 x 7-7/8 x 10-3/4 inches/254 x 200 x 275mm (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). SpecificationsHeadBinocularMagnification range3.5x-90x overall magnificationZoom objective power0.7x-4.5xEyepieces (DIN, 30mm)WH10x20mm high-eyepointZoom range26:1Field of view range3/16 to 1-1/4Optical working distanceUp to 8Microscope standPillarHead movementX-axisIllumination typeEpiscopic (reflected)Light source144-bulb led ring light with rheostatPower110V-240VMicroscopes 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. Whats in the Box? AmScope SM-1BSZ-144S stereo zoom microscope with pillar stand WH10x20mm eyepieces, 30mm, one pair 0.7x-4.5x zoom objective 0.5x Barlow lens 2.0x Barlow lens 144-bulb LED ring light with power supply (LED-144S) Eye guards, one pair Stage clips, one pair Dust cover