Obviously an installation without a garbage disposer. With a disposer, the sink has to be slightly offset instead of directly over the dw. They made the sink with either left and right hand drain holes at the rear with a nice little sloping partial ring to make it easier to get the stuff in the disposer and encourage the water to run into it. This is like the sink I found a week ago. The old metal tub dishwasher did not have the rack under the low portion at the rear, nor was the top rack on rollers. The top 1/2 rack sat on the front of the lower basket. They make a nice impromptu dish or glass drainer.