FIG. 1 is a top perspective view of a unit base showing my new design;
FIG. 2 is a bottom perspective view thereof;
FIG. 3 is a top-exploded perspective view thereof;
FIG. 4 is a bottom-exploded perspective view thereof;
FIG. 5 is a front-exploded perspective view thereof, showing the plane upon which a cross-sectional view is taken and shown in FIG. 6;
FIG. 6 is a vertical cross-sectional view thereof taken along line 6-6 of FIG. 5;
FIG. 7 is a front view thereof;
FIG. 8 is a back view thereof;
FIG. 9 is a top view thereof;
FIG. 10 is a bottom view thereof;
FIG. 11 is a left view thereof; and,
FIG. 12 is a right view thereof.
The broken lines showing of recessions in FIG. 2, FIG. 4-6, and FIG. 10 and the broken lines showing of protrusions in FIG. 3-6 are included for the purpose of showing environmental structure and forms no part of the claimed design.