High Quality Material The Concrete Screws are made of high-quality Carbon Steel, and the surface of the screw is treated with Blue Ruspert, which has strong corrosion resistance; They are hardened to a high temperature for exceptional hardness, anti-rust property and corrosion resistance. Hex Head Design Our Hex Head Concrete Screws feature a slotted Hex head that can be driven with a slotted point screwdriver or a hex bit socket. High-Low Thread Self-Tapping Masonry Screws The high-low thread design provides strong fixing ability, and the sharp tail makes drilling faster. How to Use Concrete Screws Step 1: Pre-drill a suitable hole Begin by drilling a hole using the provided drill bit - concrete screws should be embedded in the base material to a depth of 1" to 1-3/4", and ensure the hole is 1/2" deeper than the screw embedment for a smooth installation. Step 2: Secure with Concrete Screws Drive the Concrete Screw into the hole perpendicularly. Note: Excessive torsion leads to screw head separation or thread stripping in the base material. Step 3: Installation Completed The installation process is simple and convenient, you can also easily remove it when needed.