Fastener with tapered tool engaging surfaces

Claim 1

IN A FASTENER HAVING A HEAD PORTION DEFINED BY A TOP SURFACE, SAID HEAD PORTION HAVING A CENTRAL AXIS AND IS PROVIDED WITH A PLURALITY OF CIRCUMFERENTIALLY DISPOSED DRIVING TOOL ENGAGING SURFACES WHICH ARE TAPERINGLY INCLINED TO THE AXIS OF SAID HEAD PORTION, AND SAID TAPERINGLY INCLINED DRIVING TOOL ENGAGING SURFACES COMPRISE AT LEAST TWO FRUSTO-CONICAL DRIVING TOOL ENGAGING SURFACE PORTIONS HAVING EACH AN AXIS OF REVOLUTION AND WHICH AXES OF REVOLUTION ARE SPACED FROM AND PARALLEL TO EACH OTHER SO AS TO PROVIDE RELATIVE TO THE CENTRAL AXIS RADIALLY ECCENTRICALLY OFFSET FRUSTO-CONICAL PORTIONS, AND EACH OF SAID FRUSTOCONICAL DRIVING TOOL ENGAGING SURFACE PORTIONS PROVIDES A ROTARY DRIVING TOOL HOLDING WEDGING SURFACE REGION WHICH IS ANGULARLY SPACED FROM THE ADJACENT OTHER DRIVING TOOL HOLDING WEDGING SURFACE REGION, AND SAID FRUSTO-CONICAL DRIVING TOOL ENGAGING SURFACE PORTIONS PERMIT A CLOSE DRIVING TOOL ENGAGING FIT SO AS TO PRODUCE A TOOL HOLDING WEDGING ACTION THROUGH A LIMITED ROTATION OF SAID TOOL RELATIVE TO SAID FRUSTO-CONICAL TOOL ENGAGING SURFACES, HENCE A RELATIVE MINIMUM SPACING OF SAID AXES OF REVOLUTION IS REQUIRE.