In contrast to the single-slot drive, the cross recess drive (also known as a Phillips drive) offers the advantage that the screwdriver blade can no longer slip out to the side and cause damage to the workpiece. Due to the tapering of the inner flanks in the cross recess, however, an axial force occurs when the screw is tightened, which pushes the blade out of the drive. This phenomenon is also known as the cam-out effect. The cross recess H drive is also used on our window construction screws (FEX), since the screwing-in torque is not too high. What this means for you: A simple Phillips screwdriver is all you need to install your windows quickly and securely.
The countersunk head (or flat countersunk head) is the most common head geometry in the world of SPAX. It has a conical shape and, in the case of SPAX, is characterised by the 90° MULTI head. Our countersunk head screws offer the ideal compromise between maximum resistance to tightening torques and a discreet and attractive screw connection. With its polygonal underside ("pockets"), the flat countersunk head mills its own way into the wood and can therefore be countersunk into the wood cleanly and flush without having to pre-drill the screw hole. What this means for you: Flush screw insertion becomes child's play – with no need to pre-drill or countersink the screw hole.
A double-lead thread is a thread with two different thread turns. While the main thread pulls the screw into the load-bearing component as usual, a counter-rotating thread below the head ensures that the attachment is tightly fastened without any movement. The double-lead thread is used on our FEX fitting screw, which anchors window and door fittings in PVC and wooden profiles. What this means for you: Fittings are installed at the desired position steady as a rock.
The CUT point on our SPAX screws enables the ultra-fast and effective insertion of our wood screws without pre-drilling. In combination with the serrations, the arrow-shaped CUT point reduces wood splitting and tearing. The CUT point also enables extremely precise and sturdy setting of the screw tip on smooth surfaces. What this means for you: You can skip an entire work step, since pre-drilling is no longer required for most woods. Saves both your screwdriver battery and your own energy – no more annoying slipping on smooth wood and derived timber products.
Effective corrosion protection is a must for screws used for outdoor structures not exposed to the elements. For this, SPAX has developed the WIROX coating, which far outdoes conventional galvanisation in terms of both protection and durability. Our WIROX-coated screws are significantly more resistant to mechanical stress than their counterparts with chromate conversion coating. No chromium(VI) is used for WIROX, which means that even after years in an area not directly exposed to the elements, the screws are not only just as resilient, but are entirely environmentally friendly, too. Our WIROX screws are the ideal choice for all open structures without direct exposure to the elements, such as carports and pergolas. For areas with extreme weather exposure, such as decking, we continue to recommend our stainless-steel screws.What this means for you: When you use our corrosion-protected screws outdoors, you can be safe in the knowledge that your structure is well fastened – in outdoor areas not directly exposed to the elements, WIROX keeps our screws statically rigid and reliably protected over many years. So there's no need for visual inspections every year!