The Fischer DuoPower offers excellent holding values through two components: The gray component made of high-quality nylon automatically activates the optimal function principle (expansion, folding, knotting) depending on the building material for the best grip. The expansion wings of the red component support secure expansion and provide additional safety to the gray component. Simply screw in the screw and pull it correctly at the end. No over-tightening of the screw. The edge formed on the anchor head prevents the anchor from slipping into the drill hole. The included screws are perfectly matched to the Fischer DuoPower expansion anchor.