Metric Wrench Sizes Internal Serration (TX)

The internal multi-tooth screw drive has the shape of a six-beam star with the beams rounded off. The flanks run parallel to each other, so that no forces act axially to the screw. No pressing force is required to push the tool out of the screw head during the screwing process. Due to the rounded beams there are no notch effects in the profile. Very high torques can be transmitted.

The tools are marked with a T followed by a number (e.g.: T10, T15, T20,...).