4x4 Post Base Brackets, 8-Pack Carbon Steel, Black

4x4 post base brackets deliver stable, wobble-reducing support for decks, pergolas, porch railings, and pavilion posts with a fully enclosed sleeve design. This 8-pack fits nominal 4x4 wood posts (recommended 3.5 x 3.5 in) and installs on concrete or wood using included hardware. Heavy-duty carbon steel with a powder-coated black finish helps resist rust and weathering for long-term outdoor use.

• Fits nominal 4x4 posts with 3.6 x 3.6 in inner size; recommended for 3.5 x 3.5 in wood posts.


• Delivers secure, enclosed post support to reduce movement on decks, railings, and pergolas.


• Installs on wood or concrete using dual-purpose screws and expansion anchors (included).


• Includes a complete hardware kit: self-tapping screws, wood screws, expansion screws, washers, and wrench.


• Resists corrosion with powder-coated carbon steel and 2 mm wall thickness for outdoor durability.

Build cleaner, stronger post connections with post anchors designed for quick alignment and reliable load support. The wide 5.5 x 5.5 in base plate helps distribute force for a steadier feel underfoot, while pre-drilled holes simplify fastening with common drills and drivers. Ideal for new builds or upgrades on decking posts, column supports, and railing systems. Grab yours today and get your structure framed faster with the right bracket set on hand.

• Quantity: 8 pcs


• Inner dimensions: 3.6 x 3.6 in (92 x 92 mm)


• External dimensions: 3.78 x 3.78 in (96 x 96 mm)


• Base cross-section: 5.5 x 5.5 in (140 x 140 mm)


• Overall dimensions: 5.51 x 5.51 x 5.51 in (140 x 140 x 140 mm)


• Material: carbon steel


• Wall thickness: 2 mm (0.08 in)


• Finish: black powder-coated


• Net weight: 22.71 lb (10.3 kg)


• Included hardware: M8*60 self-tapping screws, φ12*60 expansion screws, M8 washers, M5*25 wood screws, double-ended wrench