The ornamental design for an attachmentdevice for a ratchet wrench, as shown and described.
FIG. 1 is a perspective view of an attachment device for a ratchet wrench showing my new design, with the ratchet wrench illustrated to show context;
FIG. 2 is a top view thereof;
FIG. 3 is a side view thereof;
FIG. 4 is a first end view thereof; and,
FIG. 5 is a second end view thereof.
It will be understood that the dashed lines presented in the drawings are for illustration purposes only and do not form any portion of the claimed design.