The ornamental design for a foldingknife handle, as shown and described.
FIG. 1 is a perspective view of the folding knife handle according to the present invention showing the knife blade (in dashed lines) in a cutting position;
FIG. 2 is the perspective view of the folding knife handle of FIG. 1 showing the knife blade (in dashed lines) in a folded position;
FIG. 3 is a front view of the folding knife handle of FIG. 1;
FIG. 4 is a rear side view of the folding knife handle of FIG. 1;
FIG. 5 is a side view of the folding knife handle of FIG. 1;
FIG. 6 is another side view of the folding knife handle of FIG. 1;
FIG. 7 is a top view of the folding knife handle of FIG. 1; and,
FIG. 8 is a bottom view of folding knife handle of FIG. 1.
The broken lines, having an evenly dashed appearance, shown in FIGS. 1-8 represent portions of a folding knife and the folding knife handle that form no part of the claimed design. The broken lines, having a dot dash dot appearance, shown in FIGS. 1, 2, 5 and 6, represent a boundary between claimed and unclaimed matter.