The ornamental design for underarm padding, as shown and described.
FIG. 1 is an isometric view of underarm padding including my new design, wherein the broken line depiction of the bottom portion is included for illustrative purposes and forms no part of the claimed design.
FIG. 2 is a top plan view of the underarm padding taken downwards from the top of the underarm padding.
FIG. 3 is a side elevational view of the underarm padding, each of the side images of the underarm padding being identical thereto, wherein the broken line depiction of the bottom portion is included for illustrative purposes and forms no part of the claimed design; and,
FIG. 4 is an end elevational view of the underarm padding, each of the end images of the underarm padding being identical thereto, wherein the broken line depiction of the bottom portion is included for illustrative purposes and forms no part of the claimed design.
The bottom surface of the underarm padding forms no part of the claimed design.