Stainless steel internal thread with a built-in expansion segment for flush surface fastenings. All anchors can also be used with threaded rods. From size M8 approved for sprinkler systems. Attachment can be loosened and tightened without loosening the anchor. Simple and safe installation with a setting tool. Small drilling diameter and short anchoring depth. Fire resistance class R120. Approved by building authorities. High holding values. Drill hole depth must be observed. The screw length must be determined according to the minimum screw-in depth and the attachment thickness. Impact A4 stainless steel may be used in dry interiors, damp interiors, exteriors, including industrial atmospheres and marine environments. For use as multiple fasteners for non-structural systems in cracked and non-cracked concrete. For spacer assemblies in combination with threaded rods. Pre-setting assembly. For professional installation, use the Impact Tool setting tool.