Hillman 1/4 in. D X 3 in. L Steel Mushroom Head Spike Anchors 50 pk

The Spike Anchor is a patented, one-piece, tamper-proof anchor for use in concrete, block or stone. The Spike anchor is formed with an "s" shaped configuration at the working end of the anchor to create an expansion mechanism. Since the anchor is pre-expanded, there is no secondary tightening position. *