The Lange Skinfold Caliper from "Beta Technology" is the most globally recognized device in sports and medical clinics. Here's a simplified explanation of how it works and how to maintain its accuracy: 1. How it Works (Why is it Accurate?) The secret to this device is its internal Symmetry Spring. Unlike cheap plastic tools, the "Lange" ensures that the pressure applied to the skin is exactly the same (10 g/mm2) whether the skinfold is very thin or thick. This consistency prevents variations in results from one measurement to another. 2. Correct Measurement Method To get the most accurate result with this device, it is recommended to follow the "Four-Site Protocol": Triceps: Back of the arm in the middle. Biceps: Front of the arm in the middle. Subscapular: At a 45-degree angle below the shoulder blade from the back. Suprailiac: Directly above the hip bone on the side. 3. Professional Usage Steps Gripping the Skin: Use your thumb and index finger to lift the skinfold (along with the fat directly beneath it) away from the muscles. Caliper Placement: Place the jaws of the device perpendicular to the skinfold, about 1 cm away from your fingers. Reading: Slowly release the handle until the pressure stabilizes, then wait just two seconds and read the number on the dial. Repetition: Take 3 measurements for each site and calculate the average to ensure accuracy. 4. Calibration The device comes with a metal piece resembling a "gauge." This piece is used to ensure the device has not lost its accuracy over time. If you place the jaws of the device on the "10 mm" mark and the indicator does not point precisely to 10, it means the device needs maintenance. 5. Who is it For? Professional Trainers: Who monitor the progress of bodybuilders or athletes. Nutrition Doctors: To accurately assess energy and fat reserves with clinical precision. Researchers: In studies requiring consistency in measurement tools.