Full size standard keratometer: Specifications: Size of measuring targets: 18x24mm Distance between measuring targets and cornea: 175mm Objective lens magnification: 1.2x Eyepiece magnification: 15x Total magnification: 18x Radius of curvature: 5.5 – 11mm 30-60 dpt Minimum surface required for measurement At 5.5mm F1.65mm At 7.5mm F2.30mm At 11mm F4.00mm Scale protractor field: 0-180° Graduation: 5° Illumination: 6V20W halogen bulb Fore and back movement: 90mm Left and right movement: 100mm Fine movement: 15mm Chin rest parts Vertical movement 30mm Dimension and weight: Packing box: 660mm x 490mm x 400mm (26” x 19 ¼” x 15 ¾”) Weight 46 lbs.