Overview

The Heavy-Duty 4x4 Post Base Bracket is an essential structural anchor engineered for securing vertical timber posts to concrete footings, wooden decks, and patio surfaces. With an exact internal dimension of 3.58 inches (91 mm), this bracket is precision-sized to fit standard North American nominal 4x4 lumber (actual 3.5" x 3.5"). Ideal for constructing decks, porch railings, pergolas, gazebos, garden fences, and mailbox posts, it elevates wood posts off wet ground to prevent moisture rot and decay while delivering rigid, wobble-free lateral stability.

Key Features

• Precision Fit for Standard 4x4 Posts: 3.58" x 3.58" (91 mm x 91 mm) internal socket accommodates standard nominal 4x4 treated timber or cedar posts without tricky planing or chiseling.
• Heavy-Gauge Structural Carbon Steel: Welded from thickened carbon steel plate with seamless exterior corner welds to resist high lateral shear loads and wind uplift.
• Wide 5.9" Square Footing Base: 5.9" x 5.9" (150 mm x 150 mm) bottom flange provides an expansive surface area for rock-solid anchoring onto concrete pads, stone pavers, or deck framing.
• Multi-Point Secure Fastening: Features four 11/32" (9 mm) pre-drilled base holes tailored for 5/16" expansion masonry anchors or heavy lag bolts, plus 8 side socket holes (2 per face) to firmly lock the wooden post.
• Weatherproof Black Powder Coating: Industrial-grade thermoset powder coating provides superior resistance against UV exposure, humidity, rain, rust, and surface chipping in all climates.
• Ground Moisture Barrier: Encloses the post base and elevates wood fibers above standing puddles and ground humidity, significantly extending the lifespan of outdoor timber structures.

Technical Specifications

• Product Type: Post Base Bracket / Post Anchor
• Internal Socket Dimensions: 3.58" x 3.58" (91 mm x 91 mm)
• Applicable Post Size: Fits standard nominal 4x4 lumber (actual 3.5" x 3.5" / 89 mm x 89 mm)
• Base Plate Dimensions: 5.9" x 5.9" (150 mm x 150 mm)
• Bracket Height: 3.54 inches (90 mm)
• Base Hole Diameter: 11/32 inch (9 mm) – compatible with 5/16" anchors or lag screws
• Side Pre-Drilled Holes: 8 holes (2 on each vertical face)
• Material: Heavy-gauge carbon steel
• Surface Finish: Matte black electrostatic powder coating
• Installation: Surface mount on concrete, pavers, or wood decking

Wholesale & OEM Capabilities

Ningbo Dimon Metal Products Co.,Ltd manufactures structural brackets, connectors, and outdoor hardware in Ningbo, China, supplying lumber yards, pergola kit builders, and building material distributors worldwide:

• Size Variants: Fabrication available for 6x6 posts (actual 5.5" x 5.5"), round posts, adjustable height standoff bases, and flush-mount corner models.
• Finish Options: Standard Matte Black architectural powder coating, Hot-Dip Galvanized (HDG) for coastal/marine exposure, and stainless steel (grade 304/316).
• Packaging & Bundling: Available in single-unit contractor packs, 4-packs, or 10-packs in heavy-duty drop-test export cartons with barcode labeling and custom fasteners.
• B2B Logistics: Factory-direct volume pricing, rapid sample production, and full container OEM/ODM manufacturing.