Mattress

FIG. 1 is a front perspective view of a mattress showing the new design:

FIG. 2 is a left-front side perspective view thereof;

FIG. 3 is a right-front side perspective view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a back view thereof;

FIG. 6 is a right-back perspective view thereof;

FIG. 7 is a left-back perspective view thereof;

FIG. 8 is an enlarged surface view thereof; and,

FIG. 9 is a bottom view thereof.

The dashed broken lines in the figures show portions of the mattress which form no part of the claimed design. The dash-dot-dot broken lines demark an enlarged detail area and form no part of the claimed design.