This is a brand new 100X (spring, oil) Achromatic microscope objective lens with high quality. It is a standard (International DIN/JIS) lens. It fits common size (DIN/JIS standard) compound / biological microscopes. We also have 4X, 10X, 20X, 40X and 60X objective lenses available. Give your microscope a boost with greater power & clarity at a fraction of cost. Features & Specifications: 100X Magnification Power DIN Standard Achromatic Objective Lens Spring Oil 20mm Mounting Thread (in diameter)