The Explore Scientific Bresser Science TRM 301 Microscope is a trinocular biological microscope made of precision parts meaning excellent imaging, good ergonomy, high stability and a modern attractive design. It is a laboratory microscope, which permits an intensive use, e.g. in medicine, biology, agriculture and industry area. Also, we can recommend it to the engaged hobbyist as his "microscope for a lifetime". A particular important feature of the TRM-301 is its ability for the Köhler illumination. This optimal illumination unbeatable bright, cool (going easy on the object), homogenous, reflex free and rich in contrast uses completely the efficiency of the microscopes optics. The Köhler illumination is standard for scientific research and microphotography. One gets it using the fixed field diaphragm and the height- and center-adjustable Abbe condenser (numerical aperture 1.25; with iris diaphragm). Naturally, the TRM-301 has the other features, which are typical for high-quality microscopes: lengthwise and cross moveable stage, ergonomic coaxial focusing knobs (concerning fine drive: 200 µm / full turn), continous dimmer, planachromatic objectives (4x, 10x, 40x, 100x-oil retractable), 10x wide field eyepieces (mounted in 30° inclined eyepiece tubes), adjustment of eye relief, diopter adjustment and the phototube.