We offer Heavy Duty Fixed Shell Anchors used for fixing of concrete, solid bricks, perforated bricks and hollow blocks. It is made of steel pressed use to concrete is appreciated. The material used is low carbon steel, stainless steel 202/304/316. The retaining power can be removed easily. When fastening the nut or screw the conical part is pulled into the Anchors, Heavy Duty Fixed Shell Anchors shells expanding it.