The ornamental design for the railing connector, as shown and described.
FIG. 1 is a top perspective view of the railing connector of the present invention.
FIG. 2 is a bottom perspective view of the railing connector depicted in FIG. 1.
FIG. 3 is a top plan view of the railing connector depicted in FIG. 1.
FIG. 4 is a bottom plan view of the railing connector depicted in FIG. 1.
FIG. 5 is a right side plan view of the railing connector depicted in FIG. 1, where the left side plan view is a mirror image of the right side plan view.
FIG. 6 is a front plan view of the railing connector depicted in FIG. 1; and,
FIG. 7 is a rear side plan view of the railing connector depicted in FIG. 1.