Simpson Strong Tie STB2-50334 1/2-Inch by 3-3/4-Inch Bolt Wedge Anchor for Cracked and Uncracked Concrete, 25-Pack Independently adjustable tri-segment clip for follow-up expansion Dual embossments on each clip segment Installs like a standard wedge anchor Head is stamped with Simpson sign and size ID No need for special bits or installation tools