Binocular head with 360-degree rotation and 45-degree incline 10x wide-field (20mm high-eye point) eyepiece provides a large field of depth 0.7x - 4.5x zoom range with a 1:6.4 zoom ratio 7x - 45x magnification range lets you get a closer look at your specimens 100mm standard working distance leaves room to observe larger objects Heavy duty rack and pinion focusing arm with tension adjustment Single arm ball-bearing boom stand Ambient illumination and optional light source