The ornamental design for the screwdriver handle, as shown and described.
FIG. 1 is a top perspective view of the screwdriver handle;
FIG. 2 is a bottom perspective view of the screwdriver handle;
FIG. 3 is a first elevation view of the screwdriver handle;
FIG. 4 is a left side elevation view of the screwdriver handle. The right side elevation view is not shown, but is identical to the left side elevation view;
FIG. 5 is a top plan view of the screwdriver handle; and,
FIG. 6 is a bottom plan view of the screwdriver handle.
The broken lines in the drawings are illustrative of environment and form no part of the claimed design.