The Fowler Stereo Zoom Microscopes with either a binocular or trinocular head have a 360-degree rotation capability and a fixed 45-degree vertical inclination to ease eye strain, -5 to +5 dioptric adjustment capabilities to compensate for the difference in viewing ability between each eye, and 55 to 75mm interpupiliary adjustment for individual eye spacing. The models in this series have 20mm 10x super widefield eyepieces, lens objectives of 0.7x to 4.5x, a zoom ratio of 6.43:1, and a working distance of 93 mm. They have upper and lower (transmitted) halogen illumination with dimmers for each light for intensity control, and interchangeable translucent and opaque stage plates with metal spring clips to secure the specimen. They have dual focus adjustment knobs and rack and pinion assembly, for controlled focusing. The trinocular model includes adapter to connect a 35mm camera (camera not included) with a standard "T" lens mount and an additional 2.5x eyepiece for photographic use for an alternative viewing option. The bodies of these microscopes are made of cast iron for durability. Stereo microscopes create three-dimensional images and are used for education, biological sciences, and manufacturing applications, among others.

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.

The Fred V. Fowler Company manufactures inspection and measurement instruments such as electronic indicators, calipers, bore gages, and digital scales. The company, founded in 1946, is headquartered in Newton, MA.