To provide a Phillips screwdriver bit structure designed to revolve without coming out, even if the shaft core line of the Phillips driver bit is fixed slantingly in relation to the vertical line of an insertion groove for bolts, etc.
The Phillips screwdriver structure is made by cutting off the tip of a blade 2 of a well known Phillips screwdriver bit by a specified distance L from the tip point, then, cutting the tip portion after cutting so that the tip portion is curved in the protruding shape from the axis of the bit shaft T by a fixed distance R from the tip of the blade 2 of 4 blades protruding axially from the Phillips screwdriver bit to form a curved face Z and providing a groove S formed in the extension portion of a groove 3 made of 4 blades 2 of the Phillips screwdriver bit, protruding radially in the tip portion after cutting.
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