FIG. 1 is a rear perspective view of a spool, showing a first embodiment of my new design;
FIG. 2 is a left-side elevational view of FIG. 1, the right-side elevational view, top plan view, and bottom plan view all being identical thereto;
FIG. 3 is a front elevational view of FIG. 1;
FIG. 4 is a rear elevational view of FIG. 1;
FIG. 5 is an exploded perspective view of a second embodiment thereof;
FIG. 6 is a left-side elevational view of FIG. 5, the right-side elevational view, top plan view, and bottom plan view all being identical thereto;
FIG. 7 is an exploded front elevational view of FIG. 2; and,
FIG. 8 is an exploded rear elevational view of FIG. 2.
The broken lines showing an electric drill device in FIGS. 1 and 5 depict environmental matter and form no part of the claimed design. The remaining broken lines represent portions of the spool that form no part of the claimed design.