The original fixing for securing structural 6 mm plywood composite insulation. For flat and pitched roofs. Hammer driven fixing for securing structural 6mm plywood composite insulation & OSB boards to flat roofs. Suitable for panels between 150mm and 185mm. Properties Fixing type: BigTwist. 20mm Headed fixing. Length: 220mm. Profile: 8mm. Pack quantity: 25x fixings. Material: zinc plated high tensile steel. Point: one point. Tension tested To Guarantee the products safety, tension is induced through the helical section by the twisting motion in the manufacturing process. Ensuring that impurities in the raw material aredetected, and any inferrior materials discarded.