FIG. 1 is a right side elevational view of a C-clamp according to my new design; FIG. 2 is a left side elevational view of the C-clamp of FIG. 1; FIG. 3 is a plan view of the C-clamp of FIG. 1; FIG. 4 is a bottom view of the C-clamp of FIG. 1; FIG. 5 is a front elevational view of the C-clamp of FIG. 1; FIG. 6 is a rear elevational view of the C-clamp of FIG. 1; and, FIG. 7 is a bottom view of the C-clamp of FIG. 1 showing the handle in a pivoted position.