FIG. 1 is a top, front, left perspective view of a first embodiment of a screwdriver bit in accordance with my design;
FIG. 2 is a front elevational view thereof, with the rear elevational view being identical thereto;
FIG. 3 is a left side elevational view thereof, with the right side elevational view being identical thereto;
FIG. 4 is a top plan view thereof; and
FIG. 5 is a bottom plan view thereof;
FIG. 6 is a top, front, left perspective view of a second embodiment of a screwdriver bit in accordance with my design;
FIG. 7 is a front elevational view thereof, with the rear elevational view being identical thereto;
FIG. 8 is a left side elevational view, with the right side elevational view being identical thereto;
FIG. 9 is a top plan view thereof; and,
FIG. 10 is a bottom plan view thereof.
As indicated in the title, the article of manufacture to which the ornamental design has been applied is a screwdriver bit. The light stippling in FIGS. 1-5 represents a contrasting color to a remainder of the body of the article of manufacture. Additionally, the heavy stippling in FIGS. 6-10 represents a contrasting color to a remainder of the body of the article of manufacture as well as a visible light effect, glow, luminescence, or fluorescence, which is a part of the claimed design. Broken lines represent portions of the article which have been shown for illustrative purposes only and form no part of the claimed design.