|  Descriptions£º 
    The high performance GL Series stereo microscopes utilize a Greenough design and feature a 1:7 zoom ratio with a 103mm working distance and a large visual field. Their parfocality allows an erect image of the observed specimens to stay in focus through repeated changes in the magnification. They feature a guidepost structure, making them lightweight, and a pair of horizontal magnification changing knobs to maximize comfort. Adding to the ergonomics is a choice of observation angle, either 45 or 60 degrees. In addition to performance and comfort, a highlight of the GL is their durability. Promoting one of the finest ball bearing guide ways in the world, the focusing mechanism is extremely robust.   Standard configurations: 
 
| Zoom ratio | 1:7 |  
| Objective zoom range |  0.65X-4.5X |  
| Eyepiece | SWF10X/22mm |  
| Working distance | 103mm |  
| Interpupillary distance adjustment | 55mm-75mm  |  
| Binocular head | inclination of 45˚ or 60˚ |  
| Diopter adjustment | +-5 diopter |  
| Optical Body Rotation | 360˚ |  
| Voltage input | 110V/60Hz  or 220V/50Hz |  
| Top halogen lamp | 6V15W  adjustable  brightness  |  
| Bottom fluorescent lamp | 5W |    GL-99B: Without the light source GL-99BI: With the light source of reflection and transmitting illuminator GL-99T: Without the light source GL-99TI: Trinocular that can be taken apart with the light source of reflection and transmitting illuminator   Technical data: 
 
| Project | Auxiliary Objective | Eyepiece | Working distance (mm) |  
| SWF10X | WFl5X | WF20X | WF25X |  
| Magnification | Visual field | Magnification | Visual field | Magnification | Visual field | Magnif-cationn | Visual field |  
| Data | 0.5X | 3.3X-22.5X | 67.7-9.8 | 4.9X-33.8X | 49.2-7 | 6.5X-45X | 40-5.8 | 8.1X-56.3X | 37-5.2 | 163 |  
| 0.75X | 4.9X-33.8X | 45.1-6.5 | 7.3X-50.6X | 32.8-4.7 | 9.75X-67.5 | 26.6-3.8 | 12.2X-84.4X | 24.6-3.5 | 117 |  
| 1X | 6.5X-45X | 33.8-4.9 | 9.8X-67.5X | 24.6-3.5 | 13X-90X | 20-2.9 | 16.3X-112.5X | 18.5-2.6 | 103 |  
| 1.5X | 9.8X-67.5X | 22.5-3.3 | 14.6X-101.3 | 16.4-2.3 | 19.5X-135X | 13.3-1.9 | 24.4X-168.8X | 12.3-1.7 | 45 |  
| 2X | 13X-99X | 16.9-2.5 | 19.5X-135X | 12.3-1.8 | 266X-180X | 10-1.4 | 32.5X-225X | 9.2-1.3 | 40 |  |