The ornamental design for a self-sealing valve for an inflatablebody, as shown and described.
FIG. 1 is a front isometric view of the self-sealing valve of the present invention;
FIG. 2 is a front view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a right-side view thereof;
FIG. 5 is a rear view thereof, symmetrical to said front view;
FIG. 6 is a bottom view thereof; and,
FIG. 7 is a left view thereof, symmetrical to said right-side view.
The broken lines shown in the drawings are for the purpose of illustrating portions of the self-sealing valve for an inflatable body and form no part of the claimed design.