Code listed for cracked and uncracked concrete, and masonry applications, the Simpson Strong-Tie® Strong-Bolt 2 wedge-type expansion anchor is an optimal choice for high-performance even in seismic and high-wind conditions. Dual undercutting embossments on each clip segment enable secondary expansion should a crack form and intersect the anchor location; this feature significantly increases the ability of Strong-Bolt 2 to carry load if the hole expands. The Strong-Bolt 2 is available in carbon steel, Type 304 and Type 316 stainless steel. Strong-Bolt® 2 — 1/4 in. x 2-1/4 in. Wedge Anchor (25-Qty) (Pack of 6).