Expanding plastic screw anchors, often referred to as wall anchors, are designed to secure objects by expanding as a screw is driven into them. Typically made from durable plastic, these anchors are inserted into a pre-drilled hole in the wall. When a screw is inserted into the anchor, it pulls the anchor wings outward, gripping the surrounding material tightly. This expansion creates a hold strong enough to support various weights, making them ideal for a wide range of applications.