The ornamental design for a ledinfraredskin-treatment device, as shown and described.
FIG. 1 is a side view of a LED infrared skin-treatment device in accordance with the present invention;
FIG. 2 is a front view of the device of FIG. 1;
FIG. 3 is a back view of the device of FIG. 1;
FIG. 4 is an enlarged bottom view of the device of FIG. 1;
FIG. 5 is an enlarged top view of the device of FIG. 1; and,
FIG. 6 is a perspective view of the device of FIG. 1.
The broken lines showing a button on the front and vents on the rear illustrate portions of the LED infrared skin-treatment device that form no part of the claimed design.