The ornamental design for ring applicator for the application of four rings, as shown and described.
FIG. 1 is a front perspective view of a ring applicator for the application of four rings in accordance with the new design, showing a break in the middle indicating that the tubular detail is of no particular length;
FIG. 2 is a right side view thereof;
FIG. 3 is a bottom view thereof;
FIG. 4 is a top view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a rear view thereof;
FIG. 7 is a front view thereof; and,
FIG. 8 is another front perspective view thereof including four rings.
The broken line showing of the three rings in FIG. 8 is for illustrative purposes only and forms no part of the claimed design.