FIG. 1 is a frontal perspective view of a full-face helmet showing my new design;

FIG. 2 is a front elevation view of FIG. 1;

FIG. 3 is a top plan view of FIG. 1;

FIG. 4 is a right side elevation view of FIG. 1;

FIG. 5 is a left side elevation view of FIG. 1;

FIG. 6 is a bottom plan view of FIG. 1;

FIG. 7 is a rear elevation view of FIG. 1;

FIG. 8 is a frontal perspective view of a second embodiment thereof;

FIG. 9 is a front elevation view of FIG. 8;

FIG. 10 is a top plan view of FIG. 8;

FIG. 11 is a right side elevation view of FIG. 8;

FIG. 12 is a left side elevation view of FIG. 8;

FIG. 13 is a bottom plan view of FIG. 8;

FIG. 14 is a rear elevation view of FIG. 8;

FIG. 15 is a frontal perspective view of a third embodiment thereof;

FIG. 16 is a front elevation view of FIG. 15;

FIG. 17 is a top plan view of FIG. 15;

FIG. 18 is a right side elevation view of FIG. 15;

FIG. 19 is a left side elevation view of FIG. 15;

FIG. 20 is a bottom plan view of FIG. 15; and,

FIG. 21 is a rear elevation view of FIG. 15.

Where indicated, dotted lines showing structure form no part of the claimed design.