Strike Anchors are designed for anchoring into concrete. Insert the Strike Anchor into a pre-drilled hole in the concrete. Set the anchor by striking the nail into the anchor. The nail expands the Strike Anchor in the concrete. Features Pin/Nail: The pin is hardened to 38 - 42 HRC to ensure the holding strength. So Strike Anchor is specialized for areas which are located in the earthquake belt .Easy operation: No special tools are required. Drilling the hole which is a little bit bigger than the diameter of the anchor that is being installed. Then use a hammer to drive the nail to expand the anchor.