The correction effect of HEADrang shows a little deviation by several factors, such as human factors (age, gender) and facial structural factors (bone and skin layer thickness, development of the masseter and buccinator, separation of jaw and cheekbones).
However, the calculation of rate of correction effect by applying those factors comprehensively show an average of 1cm decrease in the width of the left and right face after 100 days of HEADrang use.
The effect rate for the first 100 days is best, and the overall effect increases according to increased terms of use like 200 days, 300 days...
It is difficult to assess the calibration effect uniformly because it depends on the state of your facial skeleton and how steadily you use the HEADrang. You will sure obtain satisfactory effect if you continue to use it steadily.
※ The reduction effect appears faster for relatively larger faces compared to smaller ones.