The Apple Maggot adult is a fly that lays its eggs in the flesh of apples. The resultant larvae feed on the flesh of fruit while it hangs on the tree, causing the fruit to bruise and decay and finally drop before ripening.The Vitax Apple Maggot Trap contains a pheromone lure which attracts the adult males. Glued inserts prevent escape.Each trap, made from strong corrugated material, will protect 3 to 5 trees for the entire season.Each pack contains one trap, two glued inserts, a hanger and two pheromone lures.(Refills are available.)