Budget-friendly and geared for student use, the National Optical & Scientific Instruments 131-LED Inclined Monocular Microscope with Cordless LED Illumination offers up a number of attractive features. First off, as its name states, the 131-LED provides cordless, LED illumination. Simply insert 3 AA alkaline batteries for 50 hours of use. Of course, there is the option to procure a power adapter for operation from an electrical outlet.
The optical system of the 131-LED centers around 3 DIN standard objectives: 4x, 10x, and 40xR. These objectives provide 40x, 100x, and 400x magnification. Smooth, precise changes in magnification are made with the 3-hole objective turret. A monocular eyepiece set at a 45° angle, is comfortable for students to use. It also rotates 360° for use by other students.
When it comes to focusing, the 131-LED features low position coarse and fine focusing controls. Student proof safety mechanisms work to ensure that the microscope will be alive and well in the lab for years to come. A slip clutch prevents damage from over focusing, while the tension adjustment eliminates stage drift. The safety rack stop prevents damage to slides and objective lenses.