FIG. 1 is a rear, bottom and right side perspective view of a back cover for a telephone handset showing my new design;

FIG. 2 is a front, top and right side perspective view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a front plan view thereof;

FIG. 5 is a top elevational view thereof;

FIG. 6 is a rear plan view thereof;

FIG. 7 is a right side elevational view thereof; and,

FIG. 8 is a bottom elevational view thereof.