When you aerate your lawn, you are opening up the soil surface to let grass roots get the air and moisture it needs for healthy growth. The Agri-Fab 40 in. Plug Aerator penetrates deep into the soil to pull 3/4 in. dia and up to 3 in. long soil plugs. Best for easily compacted soil like clay, heavy-traffic areas such as playgrounds and sports fields and drought damaged lawns. Weight tray can hold up to 140 lbs. allowing for increased soil penetration by the 24 aerator knives.