Double Slotted Roofing Bolt Complete With Square Nut. Finish: Zinc Plated. Fully Threaded. Low Profile Cross Slotted Mushroom Head. Clearance Hole Size Is Usually 1Mm More Than The Bolt Diameter. Suitable For Both Interior And Exterior Use. Can Be Used On Many Diy Projects Other Than Roofing.PTDFORDIRRBN8160
