concrete double expansion anchor

The self-tapping property of these screws lies in their thread design. The sharp cutting edges on the screw's thread cut into the material, creating a mating thread as it is screwed in. This mechanism ensures a secure grip, minimizing the risk of stripped threads or loose connections. Moreover, due to their plastic composition, nylon self-tapping screws can be easily removed and reinserted without damaging the surrounding material, a characteristic that metal screws often lack.

...

Long tek screws, also known as 'decking screws' or 'structural screws,' are engineered to provide superior holding power and resistance against various environmental factors. Their length, which exceeds that of standard screws, enables them to penetrate deeply into materials, creating a robust and secure connection. This makes them ideal for tasks requiring substantial load-bearing capacity, such as in construction, woodworking, and machinery assembly.

...