Feature: 1. Low Power: Achromatic objective lens has a larger low magnification aperture, a brighter image and a larger field of view. The high magnification objective lens has a reduced field of view and brightness. 2. Parallel Optical Way: The achromatic microscope objective lens is a parallel optical way with no pinch angles, correcting for spherical and convergence aberrations. 3. Clear View Field: Achromatic low power objective has a clearer and sharper edge of field of view. The field of view is somewhat wider than that of a normal achromatic objective lens. 4. Fine Crafted, Universal Thread: The microscope objective lens is finely crafted with a chromium plated surface; metal for a comfortable feel. Universal 20.2mm/0.79in standard RMS thread. 5. Premium Material: Achromatic microscope objective set is made of high quality copper and optical glass, which is robust, corrosion resistant and has a high light transmission. Specification: Item Type: Achromatic Objective Lens Material: Copper, Optical Glass Magnification: 1X Numerical Aperture: 0.05mm/0.002in Applicable Models: Biological Microscope. Package List: 1 x Achromatic Objective Lens1 x Storage Case (Installed)1 x Protective Cover (Installed) Note: Please allow for some errors in manual measurements.