National 450 Series Dual Magnification Stereo Microscopes

National 450 Series Dual Magnification Stereo Microscopes. All the quality features and versatility of larger stereo microscopes, in a compact size only 12" tall. Ideal size for elementary and middle school, rugged enough for high school. Upright, unreversed image is designed for three-dimensional objects and dissection. Choose low magnification for a wide field of view, then high magnification for close-up detail. MAGNIFICATION 1x & 3x with 10x WF Eyepieces (10x & 30x Magnification) 2x & 4x with 15x WF Eyepieces (20x & 40x Magnification)  OPTICAL SYSTEM Paired widefield 10x eyepieces, left-side diopter adjustment, interpupillary adjustment from 55mm to 75mm. Eyepieces equipped with reticle holder/retainer to accept reticle with 23mm O.D. Paired objectives are parfocalled, parcentered, achromatic. Magnification changed by rotating objective turret 90 degrees, to positive click stops. Fixed head. ILLUMINATION 4-position light control: top only, bottom only, top and