With conventional, conical recesses, such as the cross recess, there is always the problem that the torque applied by the user will force the screwdriver bit upwards and out of the recess. This often results in the bit slipping out or even the total destruction of the recess (we say the screw has been "stripped"). In order to counter this slipping effect, the user needs to exert contact pressure. By using a recess with a parallel profile (such as the T-STAR or T-STAR plus), this undesirable cam-out effect and the need to apply contact pressure can be eliminated. “Stripped screws” are a thing of the past.