SU5332 served as a sort of curb diving the tile gutter (SU5331) alongside wall SU5387 from the sewer to the east, into which it drained through the small hole. This sewer slopes down toward block SU5361 on both sides, and sits at a much lower lever than the gutter 5331. The curb was necessary for safety reasons, since this area was accessible through the doorway in wall 5412.