Yes that is part of the small seeds kit. We have had some combines come with it and without it. We ran MH, MH2 and MH3 combines harvesting Kentucky Bluegrass so needed the small seed kit. Just need to loosen the bolts in the slot and open the screen up out of the way for heavy crops which we did for wheat and peas. Up high in front of the walkers is another screen to shut the air down if you have the full small seeds kit. There is one hole it pivots on and a hole to hold open and one for the down position. It is spring loaded and just pull out to twist into open or closed position. It doesn't have the adjustment slot like in your picture of the lower one.