High Quality Material: The 4X4 post base is fabricated from high-quality Q235B steel.The precision welding process ensures durability and resistance to deformation.It is sprayed with a black powder coating, making it rust and corrosion resistant.Post Base Features: We designed the bottom of the 4X4 post bracket with a soak-proof feature.This ensures the bracket's sturdiness while simultaneously preventing the wood post from rotting due to long-term water exposure, thus prolonging the wood's service life.Wide Application: The post bracket is tailored for wood posts with an actual size of 3.6 inches x 3.6 inches and can be employed to support stair railings, deck brackets, mailbox post brackets, and fences.Standard Size: Each post base measures 5.4 inches (L) x 4.32 inches (W) x 4 inches (H), with an inner diameter of 3.6 inches x 3.6 inches.Set Includes: 4 Pcs post base with 24 expansion anchors,24 large self-tapping nails,24 Black Self-Tapping Nails and 1 wrench. Feel free to contact us for any installation or other inquiries.