Binocular and trinocular models have 15x eyepieces to achieve 21x–135x continuous zoom magnification at working distance of 3.3 in. With optional 20x eyepiece, magnification from 28x–180x is possible. Eyepieces, set at 45° angle, have interpupillary distance adjustment, and each eyepiece tube also has diopter adjustment. Customizable or available as complete system, microscopes feature click-stop zoom adjustments and multi-coated optics. Trinocular body adds one-touch fine focus adjustment.