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 elevation view of the insulating cup sleeve shown in FIG. 1 (the rear elevation view of the insulating cup sleeve is an identical image of the view shown in FIG. 3);
FIG. 4 is a right side elevation view of the insulating cup sleeve shown in FIG. 1 (the left side elevation view of the insulating cup sleeve is an identical image of the view shown in FIG. 4);
FIG. 5 is a top perspective view of the design of a second embodiment of the insulating cup sleeve showing the new design;
FIG. 6 is a bottom perspective view of the insulating cup sleeve shown in FIG. 5;
FIG. 7 is a front elevation view of the insulating cup sleeve shown in FIG. 5 (the rear elevation view of the insulating cup sleeve is an identical image of the view shown in FIG. 7); and,
FIG. 8 is a right side elevation view of the insulating cup sleeve shown in FIG. 5 (the left side elevation view of the insulating cup sleeve is an identical image of the view shown in FIG. 8).
The broken lines shown in the drawing views are included for the purpose of showing environmental structure that forms no part of the claimed design.