The SPAX typical drive T-STAR plus is a so-called internal hexagon. This shape increases the contact area of our T-STAR plus, allowing the T-STAR plus bits to fit optimally in the screw head. The best possible power transfer from the screwdriver to the screw through T-STAR plus enables quick work, significantly more efficiently than with any other drives. The countersunk head (or flat countersunk head) mills a recess into the wood with its polygonal underside ("pockets") and can therefore be sunk without additional countersinking of the screw hole. The countersunk head sits flush with the surface. Unlike partial threads, the full thread extends over the entire length of the screw. The more thread turns a screw has, the greater the tensile and compressive forces that can be transferred from the screw to the wood. Our full-thread screws are primarily used for highly stressed wood connections. The S-tip is characterized by the fact that the thread is formed all the way to the front flanks. When you position the screw and start the cordless screwdriver, this thread immediately grips in the wood and pulls the screw in effortlessly. This allows for fast work without scratching the workpiece due to the screw tips slipping. With WIROX, SPAX has developed a coating that is far superior to galvanization in terms of corrosion protection. WIROX does not use chromium (VI), and the screws remain just as durable and environmentally friendly even after years in non-directly weathered outdoor areas. WIROX screws are the first choice for all open structures without direct weather exposure, such as carports or pergolas. For direct weather exposure, such as on terraces, we recommend our screws in stainless steel.