The power transmission from the nuts to the screw head is not via the corners, but via the flanks. This ensures higher power transmission, plus the sensitive edges of the nut remain intact. https://elecena.pl/product/27172137/toolcraft-820775-1-2-quot-drive-socket-21mm 2024-11-07 https://elecena.pl/product/27172137/toolcraft-820775-1-2-quot-drive-socket-21mm 2025-07-30