The ornamental design for an insulating cupsleeve, as shown and described.
FIG. 1 is a top perspective view of the design of an insulating cup sleeve showing the new design;
FIG. 2 is a bottom perspective view of the insulating cup sleeve shown in FIG. 1;
FIG. 3 is a front elevational view of the insulating cup sleeve shown in FIG. 1;
FIG. 4 is a right side elevational view of the insulating cup sleeve shown in FIG. 1;
FIG. 5 is left side elevational view of the insulating cup sleeve shown in FIG. 1;
FIG. 6 is a rear elevational view of the insulating cup sleeve shown in FIG. 1;
FIG. 7 is a top perspective view of the second embodiment of the design of an insulating cup sleeve showing the new design;
FIG. 8 is a bottom perspective view of the insulating cup sleeve shown in FIG. 7;
FIG. 9 is a front elevational view of the insulating cup sleeve shown in FIG. 7;
FIG. 10 is a right side elevational view of the insulating cup sleeve shown in FIG. 7;
FIG. 11 is left side elevational view of the insulating cup sleeve shown in FIG. 7; and,
FIG. 12 is a rear elevational view of the insulating cup sleeve shown in FIG. 7.
The broken lines shown in the drawing views are included for the purpose of showing environmental structure or boundary lines that forms no part of the claimed design.