Base

FIG. 1 is a front view of a base showing the claimed design;

FIG. 2 is a rear view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a bottom view thereof;

FIG. 5 is right view thereof;

FIG. 6 is a left view thereof;

FIG. 7 is top, front left perspective view thereof;

FIG. 8 is top, front right perspective view thereof;

FIG. 9 is top, rear left perspective view thereof; and,

FIG. 10 is top, rear right perspective view thereof.

The broken lines in the drawings depict unclaimed subject matter that forms no part of the claimed design.