FIG. 1 is a perspective front and side view of an adjustable cover, showing my new design;
FIG. 1A is an enlarged isolated detail view of FIG. 1;
FIG. 1B is an enlarged isolated detail view of FIG. 1;
FIG. 1C is an enlarged isolated detail view of FIG. 1;
FIG. 2 is a bottom view of FIG. 1;
FIG. 2A is an enlarged isolated detail view of FIG. 2;
FIG. 2B is an enlarged isolated detail view of FIG. 2;
FIG. 3 is a front view of FIG. 1;
FIG. 3A is an enlarged isolated detail view of FIG. 3;
FIG. 3B is an enlarged isolated detail view of FIG. 3;
FIG. 4 is a side view of FIG. 1;
FIG. 4A is an enlarged isolated detail view of FIG. 4;
FIG. 4B is an enlarged isolated detail view of FIG. 4; and,
FIG. 5 is a top plan view of FIG. 1.
The broken lines in the drawings are included for the purpose of illustrating unclaimed environment, and form no part of the claimed design.