Calculation of cylindrical tension springs in accordance with DIN 13906-01. Includes sizing (through specifying spring torques and installed dimensions) and calculation review of tension springs. Database with the most important spring materials. Database with wire diameters in accordance with DIN 2076, 2077, EN 10270-1. Presentation of the spring characteristic curve. Tolerances, main dimensions, eyes in accordance with DIN 2076, 2077, EN 10270-1.