Female Threaded Anchor for Concrete Zinc 1/4-20 [Drop In] Drill Bit size 5/16

A zinc plating provides corrosion resistance in wet environments. Also known as drop-in anchors, these are often used for overhead applications because the anchor's internal plug expands in four directions to hold the anchor firmly inside the hole before inserting a threaded rod or bolt. To install, place the anchor into the hole, insert the required installation tool (sold separately) into the anchor, and drive with a hammer until the thicker portion of the tool makes contact with the anchor. When installed, anchors sit flush with the surface. Pull-out strength and shear strength values are 25% of the ultimate values.