... Backward Quadruple Nosepiece Polarizing Microscope NP-400BWith the features of streamline and stable frame, easy operation and complete ... Graduation 0°90°AABertrand LensBertrand Lens , Sliding in/ out of Optical pathAAOptical CompensatorλSlip (first class red), 1/ ... FilerAAFocusingCoaxial Coarse and Fine Adjustment, Range 28MM, Fine Division 0.002AAPolarizeSliding in/out of Optical Path ,Located on the ...