2 pack Bolt Down Bracket KitMount your pergola safely and securely to a wood deck or cement patioEasy Mounting, lasting installation, safe and rigidThe Bolt Down Brackets are guaranteed for 5 years against defects.Note: DO NOT use the bolt down bracket system for installing the pergola over concrete pavers, patio stones, or interlocking bricksAdditional Materials Are RequiredMaterial: Galvanized steel