Microscope Head Trinocular Head 3.5‑100X Bifocal Continuous Zoom Stereo Microscope Head Item Type: Microscope Head Head: 45° tilt, 360° rotation, three eyes in focus. Eyepiece: 30mm / 1.18in(approx.) ultra wide angle high eyespot WF10X/22. Target: 0.7-5X Zoom Range: 6.5:1 Three Eye Port: 25mm / 0.98in(approx.) photo port Pupil Spacing: Approx. 54 ~ 76mm / 2.13 ~ 2.99in Field of View: Approx. 33mm / 1.3in Working Distance: 7X-50X, that is, 100mm / 3.94in(approx.). When using 0.5X objective 3.5X-25X, that is, 200mm / 7.87in(approx.). When using 2X objective 14X-100X, that is, 50mm / 1.97in(approx.). Head Mounting Diameter: Approx. 76mm / 2.99in Accessory Installation Diameter: 1-7/8in, that is, 48mm / 1.89in(approx.) female thread. Features: 1. 3.5X to 100X continuous zoom magnification. 2. 45 degree tilt three eye analog focal head with ultra wide angle high eye eyespot eyepiece. 3. Three eye port with adding photo or video functions. 4. 30mm ultra wide visual field WF10X eyepiece, 20mm visual field. 5. High resolution with high flatness and contrast. 6. Clear stereoscopic upright image under wide field of vision. 7. Clear original image with true color. 8. Large working distance, accurate alignment, ensuring no fatigue viewing. 9. All optical glass elements. 10. Accurate frosted glass lens. 11. Adjustable pupil spacing.