Traditional elastic band is used to fasten the upper arm, the interface between the elastic band and the arm is so small that intensify of pressure becomes large.
· It may cause the following results: arm congestion and subsidence of blood vessel. Even worse, it may cause the change of some analyses in blood, such as creative phosphate, uric acid and acid and finally influence blood sample. It is equipped with wide stretch strap so that the intensity of pressure largely decreases to the modest degree. It can avoid congestion at the largest degree, easy feeling and improve blood sample.