SatelliteSale General Purpose 5/16' Outer Diameter X 2' Long, 7/16' Hex Head Lag Bolt Zinc Plated Screws are specially produced and designed for wood and concrete(anchors required) installations. Our lag screw can be used for the roof, wall, deck, and indoor applications. Zinc-plated and produced of Grade 5 metal SatelliteSale Lag Bolts feature increased durability alongside with oxidation resistance. Suitable for outdoor installation. Can be used to install tripod feet, satellite mount mast, antenna bases, or any other object you want to attach to your roof, to the side of your house, to the deck, and so on. Please, keep in mind that hardwoods should always be pre-drilled with a pilot hole to avoid splitting the wood. In addition, we recommend using lag shield anchors to properly secure the lag bolts inside the concrete. It comes in a pack of 100 pieces, and all SatelliteSale products are ensured with an unbeatable lifetime warranty!