System 373 Stereo-Zoom Microscopes feature 10X super wide-field eyepieces that provide a magnification range of 7X to 45X with a working distance of 8". The 24" horizontal dual boom ball-bearing extension can be adjusted to virtually any vertical and horizontal angle to provide unlimited positioning. The scope sturdy, cast aluminum alloy housing rotates 360? in focus mount. Dual graduated knobs on both sides of the head control the zoom adjustment.