The ornamental design for a pickguard, as shown and described.
FIG. 1 is a perspective view of a pickguard showing my new design; and,
FIG. 2 is a top plan view thereof.
The bottom plan view thereof, as well as the right, left, front, and rear elevational views thereof, are unornamented and form no part of the claimed design.
The guitar shown in broken lines forms no part of the claimed design and is included soley to depict the environment in which the claimed pickguard is normally used. The pickguard is affixed to the top surface of a guitar and is essentially two-dimensional, having length and width, but only nominal height.