These Forgefix double slotted roofing bolts are supplied with square nuts and have a low profile mushroom head. Their bright zinc plated finish increases resistance to corrosion. The bolts are suitable for both interior and exterior use and can be exposed to weather conditions without the risk of rusting. Used in many applications beyond roofing when joining products together. Use clearance drill sizes 1mm larger than bolt diameter. Zinc coatings prevent oxidation of the protected metal to create a longer lasting finish by forming a barrier. This protective layer ensures durability and extended product life. Each pack contains 25 Roofing Bolts, size M6 x 70mm, with a zinc plated finish.