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the Phillips head screw and screwdriver combination was designed specifically to cam out, as at the time of its invention torque sensing automatic screwdrivers did not exist. The Phillips design is auto-centering, that is, the screw does not slip off the screwdriver, unlike a normal slotted-head screw or flat-head screws, but cams out once the screw has been driven home. These properties were used to speed up automobile production in the USA in the early years of the industry.

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