Anchors for Glazing: Halfen systems have been successfully specified and used on hundreds of projects to anchor glazed curtain wall and other window systems. Anchor channels for stick and unitized systems have been developed for a variety of conditions including edge-of-slab, top-of-slab, and under-slab anchoring. Anchor channels for very thin slabs, high loads, and blast loads have been custom-engineered for many low-rise and high-rise applications.