Almost, but not quite
Those are actually "double square" or "double Robertson" capscrews. Torx is a hexalobular or "6lob" internal drive. The screw heads in the opening screen visual have eight points.
A Canadian inventor, Robertson patented his unique tapered square drive for screws in 1908-09; they were much more common in Canada than the so-called "Phillips" head. Apparently, when he refused to license his design, others began to develop "improved" versions, namely the double square and triple square versions. They have been around for a long time; an other-than-casual look around the U-505 reveals numerous uses.
|