1. As a result of generalizing the experimental data, it is shown to be possible to select the initial volume Vo as the index of the type of hose and the relative change in volume V as the pliability index. 2. With the chosen indices V0 and V, linearization of the elastic characteristic of hydraulic connectors by means of Eqs. (7) and (8) is possible with an error not exceeding 1.5%; this significantly simplifies the calculations. 3. The recommendation for more accurate calculations is to measure the actual volume or use Eq. (6) under the condition of measuring the actual length of the hose. 4. In special cases, where it is necessary to take account of the initial nonlinear section of the characteristics, Eq. (5) may be recommended.