What is claimed is the ornamental design for a bottle insulator with a resealable cap, as shown.
FIG. 1 is a front elevation view of a bottle insulator with resealable cap, embodying my new design, the rear view being identical thereto;
FIG. 2 is a side elevation view thereof;
FIG. 3 is a top plan view thereof;
FIG. 4 is a bottom plan view thereof;
FIG. 5 is a perspective view thereof; and,
FIG. 6 is another side view thereof, shown in use.
The broken lines in the drawings that represent the portions of a bottle are for the purpose of illustrating environment that forms no part of the claimed design.