Typical hardness on diameters 1/4 to 2 1/2 inches is HRC 33-39

1/2-13 x 9 Grade 5 Hex Cap Screw Zinc Plated

7/8-9 x 4 Hex Cap Screw SS 18-8 (A2)

1-8 x 2 1/2 Grade 8 Hex Cap Screw Yellow Zinc Plated

1-8 x 3 1/2 Grade 5 Hex Cap Screw Zinc Plated

1/4 x 3 Mushroom Spike Zinc Plated (100) 3/4-16 Grade 5 Hex Cap Screws Zinc Plated Typical hardness on diameters 1/41 4 x 3 Mushroom Spike Zinc Plated (100) . The Spike anchor is a patented, one piece, tamper proof, vibration resistant anchor for use in concrete, block, brick or stone. Several head styles and anchor materials are available. 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 operation required which greatly