Toolbox support frame with telescoping legs and crossbars

FIG. 1 is a perspective view of a toolbox support frame with telescoping legs and crossbars showing my new design;

FIG. 2 is a side elevational view thereof, the elevational view of the opposite side being identical thereto;

FIG. 3 is an end elevational view thereof, the elevational view of the opposite end being identical thereto;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof; and,

FIG. 6 is a reduced side elevational view showing the toolbox support frame with telescoping legs and crossbars in use; the broken lines depict environmental structure for illustrative purposes only and form no part of the claimed design.