These are a pair of brand new extreme widefield high-eyepoint 30mm WF30X microscope eyepieces with extreme wide field of view. They are Achromatic (International DIN/JIS) standard size with outside diameter of 30 mm. They fit most common size microscopes including Leica, Zeiss, Nikon and Olympus. Give your microscope a boost with greater power & clarity at a fraction of cost. Features & Specifications: 30X Magnification Power 9mm Super Wide Field of View 30mm Mounting Size (in diameter) High Eye-point Design