195 AllSteel Achromatic Objective Lens For All Biological Microscopes (100X) Features: Made of all-steel material, it is durable and hard to wear. The magnification is adjustable and the image is clear, making it easy to observe the texture and structure of tiny things. There are six objective lenses available, 4X, 10X, 20X, 40X, 60X, 100X. Each objective is equipped with a single plastic box for easy storage. This product is dedicated to a variety of biological microscopes, using a Standard RMS interface 20.2mm. Specifications: Condition: Material: Steel Standard: Standard RMS interface 20.2mm Type: 4X, 10X, 20X, 40X, 60X, 100X Achromatic Objective Lens (Optional) Magnification  Numerical aperture  Working distance  Thickness of the coverslip  Impregnating medium  Spring  4X  0.1mm 18mm 0.17mm No  No  10X  0.25mm 7mm 0.17mm No  No  20X  0.4mm 0.55mm 0.17mm No  Yes  40X  0.65mm 0.53mm 0.17mm No  Yes  60X  0.65mm 0.13mm 0.17mm No  Yes  100X  1.25mm 0.13mm 0.17mm Oil  Yes  The use of various objectives: 4X: Observe insects, banknotes, repair electronic motherboards, etc. (can be viewed separately), and the imaging is clearer than the magnifying glass. 10X: Repairing fine electronic components, small antiques, etc. (can be viewed separately), the imaging is clearer than the magnifying glass. 20X: Observe aphids, aquatic products, silkworms, etc. 40X: Observe cells, sperm, eggs, artificial insemination, etc. 60X: Observe cells, sperm, eggs, artificial insemination, crude bacteria, etc. 100X: Observe medical tests, blood tests, bacteria, scientific research, students see specimens, etc. Package list: 1 * Achromatic Objective Lens