The ornamental design for a wireless pressurestrap, as shown and described.
FIG. 1 is a perspective view of my novel and non-obvious design for a wireless pressure strap.
FIG. 2 is a perspective view of the wireless pressure strap; and,
FIG. 3 is a perspective view of the pressure strap with the broken line showing of environmental association matter being for illustrative purposes only and forming no part of the claimed design.