Ribbed ballast housing

FIG. 1 is a front view for a ribbed ballast housing showing my design;

FIG. 2 is a bottom plan view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a top view thereof;

FIG. 6 is a back view thereof;

FIG. 7 is a top perspective view thereof; and,

FIG. 8 is a bottom perspective view.

The broken line showing of the luminaire is for illustrative purposes only and forms no part of the claimed design.