Features:Made of high quality 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: 100 percent Brand NewMaterial: SteelStandard: Standard RMS interface 20.2mmType: 4X, 10X, 20X, 40X, 60X, 100X Achromatic Objective Lens (Optional)MagnificationNumerical apertureWorking distanceThickness of the coverslipImpregnating mediumSpring4X0.1mm18mm0.17mmNoNo10X0.25mm7mm0.17mmNoNo20X0.4mm0.55mm0.17mmNoYes40X0.65mm0.53mm0.17mmNoYes60X0.65mm0.13mm0.17mmNoYes100X1.25mm0.13mm0.17mmOilYesThe 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 x Achromatic Objective Lens.