FIG. 1 is an upper front right perspective view of a mailbox showing my new design.

FIG. 2 is an upper rear right perspective view of the design of FIG. 1.

FIG. 3 is an upper front left perspective view of the design of FIG. 1.

FIG. 4 is an upper rear left perspective view of the design of FIG. 1.

FIG. 5 is an enlarged front end view of the design of FIG. 1.

FIG. 6 is an enlarged rear end view of the design of FIG. 1.

FIG. 7 is a right side view of the design of FIG. 1.

FIG. 8 is a left side view of the design of FIG. 1.

FIG. 9 is a top view of the design of FIG. 1; and,

FIG. 10 is a bottom view of the design of FIG. 1.

The broken lines showing the fasteners, mounting holes, bottom frame support and flag represent environmental components of the mailbox and form no part of the claimed design.