Trinocular observation head, siedentopf observation head inclined at 45o.diopter adjustment ring on ocular tube.interpupillary distance from 50mm to 75mm.co-axial and fine focusing system with slide traveling on ball bearing guide ways.observation on trinocular head, compensation(inclined 30 degrees)triple plate for X and Y movement of workstage.anti-fungal coated objectives. inner locating ball bearing nosepiece.