Lexicon DIY-Knowledge

Screwdriver bits


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The accessories for screwdrivers are screwdriver blades or screwdriver bits. In addition to their shapes, which reflect the available screw types, the material from which they are made and the production method play a decisive role for quality and application.

Material properties

Extra hard
With Extra Hard, Slotted medium and large size, Phillips and Pozidriv bit shapes are produced in a special cold forming process. This way the bits become especially tough with a high load capacity. The Slotted small size, internal Torx and internal hex bit shapes are milled. This achieves very high precision. All Extra Hard bits are hardened throughout. The hardness is 59 to 63 HRC (Rockwell). Slotted, Phillips and Pozidriv bit shapes have a torsion zone. It cushions torque peaks and makes the bit more resistant to breakage. With the slim shank, smaller screw heads can be sunk in soft materials. Every bit is stamped, which gives information about the manufacturer, the bit shape and size as well as the country of origin.

The basis for a MAXgrip is an Extra Hard bit. All good characteristics of Extra Hard are therefore included.
Additionally MAXgrip has the following characteristics: The bit shape surface is blasted with aluminium oxide (Corundum). The result is a micro-rough surface. Best grip in the screw head results in a reduction of ejection forces. The surface is coated with Titanium Nitride (TiN). This very hard layer is wear proof. The micro-rough surface remains intact for very long thanks to this particular surface treatment.