J Bolts, or Hook Bolts, are typically used for roofing applications. They host a hooked bottom which is designed to hook onto rebar embedded in concrete and threading on the top of the fastener.They are a very common and durable fastener used by construction workers when erecting a new building. Homeowners also often use these fasteners when building garages, foundations or when attaching walls to concrete.Manufactured in mild Steel Zinc Plate and Stainless Steel as standard.Available from Fastenright in sizes from M6 to M8 and lengths ranging from 40mm to 300mm.Non-standard sizes, materials and finishes are available to order as specials, including small volume manufacture, modifications and custom parts made to drawings.