TRU Trinocular â€" allows the user to simultaneously view images on screen and through the eyepieces. These microscopes feature 10X super wide-field eyepieces that provide a magnification range of 7X to 45X with a working distance of nearly 8 in. (203 mm). The scopesâ€™ sturdy, cast aluminum alloy housing rotates 360º in its focus mount. Dual graduated knobs on both sides of the head control the zoom adjustment.