Infinite Optical System. Compensation Free Trinocular Head, Inclined at 30°, 360° Rotatable. Interpupilary Distance 48-75mm. Compensation Free Binocular Head, Inclined at 30°, 360° Rotatable. Interpupilary Distance 48-75mm. Extra Wide Field Eyepiece EW10×/ 20. Inverse Quintuple Nosepiece. Infinite Plan Achromatic Objective 4×、10×、40×、100×. Swing Condenser N.A.0.9/ 0.25. Coaxial Coarse & Fine Focus Adjustment, Fine Division 0.002mm. Double Layers Mechanical Stage 185×142mm,. Moving Range 75×55mm. External Illumination, Halogen Lamp 12V/ 50W. Green LED Pointer , Brightness Adjustable.