J-300 inverted metallurgical microscope ,imaging clearly, wide field of vision J-300,The whole design accord ... is an important tool for study materials, Applicable to industrial and mining enterprises, institutions of higher learning and scientific research ... /18mm, WF12.5X15mm4)Objectives:Special use metallurgical objectives, flat-field achromatic objective lens 4X ,10X ,40X ,100X(oil)5)Changer: ...