1pc 1/4x2-1/4 wdg anchor. Use for fastening into solid concrete. Corrosion-resistant, 1-piece stainless steel expander clip. Supplied with nut and washer. Zinc coating. For normal exterior use. Not recommended for highly corrosive areas (salt spray) or treated lumber. Drill hole same size as anchor, inset anchor and tighten. 1/4" x 2-1/4", 1-piece