The terms 3% and 4% often relate to the percentage of the anchor bolt’s yield strength in relation to the concrete’s compressive strength. For example, a 3% concrete anchor bolt means that the bolt can withstand loads up to 3% of the concrete's yield strength, while a 4% bolt can handle loads up to 4%. This distinction is vital for engineers and contractors, as it influences load calculations, safety factors, and the overall design of the structure.

The white wafer head of these self-drilling screws is characterized by a broad, flat surface that provides a wide bearing area. This design helps distribute the load more evenly, reducing the risk of damage to the material being fastened. The head is typically finished in a white coating that not only enhances aesthetic appeal but also offers a degree of corrosion resistance, which is particularly beneficial in outdoor applications or areas exposed to moisture.

- Framing and Structural Work In construction, Tek screws are often used to frame walls, secure roof trusses, and install sheathing panels. They help create strong structural connections that are essential for the integrity of the building.