In the first step of the ID Match, the intertrochanteric distance is measured, i.e. the distance between the bony prominences of the right and left femoral head, followed by the diameter of the thighs.
Finally, the pelvic rotation or Pelvic rotation determined.
The Smart Caliper uses the first two values to calculate the XQ index. The index found in this way describes the distance between the thighs, from which the best saddle shape can be determined.
The determined value of the pelvic rotation is used to determine the type of saddle that allows for the best comfort. Put simply: the higher the pelvic rotation, the greater the pressure on the perineal area.
Selle Italia builds saddles in two different widths, labeled S and L. S are the narrow models, which are also slightly narrower in the middle than L saddles. Based on the result of the pelvic rotation measurement, either a saddle with no hole, a small hole or a large hole is recommended.