The inexpensive basic model with all the important basic functionsSpecs: - Diopter wheel with 29 corrective lenses Plus 1-10, 12, 15, 20, 40 Minus 1-10, 15, 20, 25, 30, 35 - Easy-to-operate aperture hand-wheel with semi-circle, small/medium/large circle fixation star, slit and red-free filter with contrast-enhancing effect - Optimized high-performance optics with aspherical condenser lens - Parallel beam path - Dust-proof |