The SM-4B is a heavy-duty, highly-flexible microscope designed for biological and industrial applications. This model is especially popular in the QC, repair and engraving industries thanks to its ease-of-use and reliability. With its wide zoom range and double-arm boom-stand, this model will become an indispensable instrument in any workshop or lab. OpticsThe stereo optics provide clear, sharp images with excellent focus-depth and a large working-distance.