Amazon
Inside square (Robertson) drive 12.5 = 1/2″ or outside hexagon 24 mm Drive: Square, hollow 12.5 mm (1/2 inch) HAZET – Qualitytools for the professional
Inside square (Robertson) drive 12.5 = 1/2″ or outside hexagon 24 mm Drive: Square, hollow 12.5 mm (1/2 inch) HAZET – Qualitytools for the professional