These leaf and lawn vacuums have a plastic elbow and blower exit adaptor that is connected to the top of the shredding chamber. The plastic can crack, allowing stones, large sticks, and other material to puncture the plastic. This creates the possibility that pieces of plastic or other debris can fly upward toward bystanders or the operator. When this occurs, the potential for personal injury or property damage exists. This is more prone to occur when the outside temperatures are below 35 degrees.