These 11mm bi-hex nut drivers are essential for fixing cladding and roofing bolts on modern commercial buildings. Specially designed for use on coated fixings, the driver fits a standard drill using the Quick-Chuck method. 11mm Bi-Hex for cladding & roofing tech screws with moulded caps.Designed especially for use on the coated fixings used on the roof and cladding of modern commercial buildings. Manufactured from Chrome Vanadium. Also available individually, please see Kamasa Part No. 55932.