The ornamental design for padlock bumpers, as shown and described.
FIG. 1 is a perspective view, taken from the front, top, and right side, of padlock bumpers in accordance with our new design;
FIG. 2 is a perspective view, taken from rear, bottom, and left side, of the padlock bumpers shown in FIG. 1;
FIG. 3 is a front elevational view of the padlock bumpers shown in FIG. 1, the rear elevational view being identical thereto;
FIG. 4 is a right side elevational view of the padlock bumpers shown in FIG. 1, the left side elevational view being identical thereto;
FIG. 5 is a top plan view of the padlock bumpers shown in FIG. 1; and,
FIG. 6 is a bottom plan view of the padlock bumpers shown in FIG. 1.
The portions of the figures shown in phantom lines are not part of the claimed design, but are shown only to illustrate the context and environment of the claimed design.