The Powers Tapper+ 1/4" X 3-3/4" Concrete Screw Anchors w/ Phillips Flat Heads (100/BX) (2770SD) are for light to medium duty applications in concrete, masonry block, brick, and wood base materials. They are fast and easy to install and provide a neat, finished appearance. Each Tapper+ screw anchor is engineered with matched tolerance drill bits and installation tools designed to meet the needs of the user and also provide optimum performance. The Tapper+ features a gimlet point for self-drilling into wood base materials without pre-drilling.