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