FIG. 1 is an isometric view of the water supply tube showing my new design, with connecting brackets shown in broken lines. The broken line showing of the connecting brackets is for illustrative purposes only and forms no part of the claimed design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a left elevational view thereof; and,

FIG. 7 is a right elevational view thereof.