The Harpenden skinfold caliper is the most accurate, tested, prestigious, and scientifically advanced skinfold caliper in the world. Designed in 1958, the Harpenden Skinfold Caliper has been used on projects of international importance. It is the only caliper CE marked under the Medical Devices Directive 93/42/EEC for a Class 1 Device with Measuring Function and is calibrated using masters traceable to National Standards. SPECIFICATIONS:Weight (with case): 3 pounds (1.8 kilograms); Dial Graduation: 0.20 mm; Measuring Range: 0 mm to 80 mm; Measuring Pressure: 10 gms/mm2 (constant over range); Accuracy: 99.00 percent; Repeatability: 0.20 mm; Recommended by ISAK. ACCESORIES: Includes calibration dowel to certify calibration. Note that a cylindrical dowel (rather than a rectangular block) is necessary to accurately certify calibration because of the angle at which the tips come into contact.