The ornamental design for a heat-dissipation unit, as shown and described.
FIG. 1 is a perspective view of a heat dissipation unit showing our new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a top view thereof;
FIG. 7 is a bottom view thereof;
FIG. 8 is an enlarged view of the portion, labeled ‘8’ in FIG. 1; and,
FIG. 9 is a perspective view thereof, shown in use with an environmental fan module thereon.
The ornamental design which is claimed is shown in the drawings as solid lines and surfaces having surface shading. The broken lines in FIG. 9 showing the additional fan module depict environmental structure only and form no part of the claim design. The broken lines consisting of a long dash and two short dashes depict reference to the enlargements shown in FIGS. 1 and 8 and form no part of the claim design. The broken line consisting of a long dash and one short dash defines the boundary of the claim design, which extends to the boundary but does not include the boundary. All other broken lines in the drawings form no part of the claimed design.