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Inside square (Robertson) 12.5 = 1/2″ or outside hexagon with bore 24 mm Drive: Square, hollow 12.5 mm (1/2 inch) HAZET – Safety and precision due to minimal manufacturing tolerances
Inside square (Robertson) 12.5 = 1/2″ or outside hexagon with bore 24 mm Drive: Square, hollow 12.5 mm (1/2 inch) HAZET – Safety and precision due to minimal manufacturing tolerances