Simpson 8d x 2-1/2" Annular Ring Shank Box Nail in 316 Stainless Steel is a professional-grade fastener engineered for demanding outdoor and coastal construction applications. Built by Simpson from Type 316 stainless steel, this box nail delivers outstanding corrosion resistance in saltwater-exposed environments, marine structures, and permanent wood foundation assemblies where long-term holding power is critical. The annular ring shank design locks into wood fibers to resist withdrawal forces, making this nail a trusted choice for decking, siding, and structural applications where a standard smooth-shank nail simply won't hold.

Key Features

• Type 316 stainless steel construction - provides superior corrosion resistance compared to standard stainless grades, making it the right choice for seaside, marine, and high-humidity environments where lesser materials would fail prematurely.
• Annular ring shank - the ringed shank profile bites into wood fibers and dramatically increases withdrawal resistance, locking the nail in place under stress, vibration, and seasonal wood movement.
• Full round head with checkered pattern - the checker-patterned head blends with wood grain, reduces glare from sunlight, and accepts surface finishes, delivering a clean, professional appearance on exposed decking and trim.
• Diamond point tip - drives cleanly through wood with minimal splitting, reducing waste and rework on finish-sensitive applications.
• 12-gauge, 8d, 2-1/2" length - the 0.113" shank diameter and 1/4" head diameter strike the right balance between holding strength and reduced wood splitting typical of box-nail geometry.
• Recommended for permanent wood foundations (ANSI/AF&PA) - meets the requirements of the ANSI/AF&PA Permanent Wood Foundations Design Specifications, giving builders confidence in code-relevant applications.
• Made in the United States - domestic production supports consistent quality standards and reliable availability for professional contractors.

Why This Product

• Purpose-built for coastal and marine environments - Type 316 stainless steel is the preferred alloy where salt air, salt spray, and moisture would corrode standard galvanized or Type 304 fasteners, making these nails the correct long-term solution for seaside structures and docks.
• Holds tighter than smooth-shank nails - the annular ring shank provides measurably higher withdrawal resistance, meaning fastened assemblies stay tight over time even as lumber expands and contracts with seasonal moisture changes.
• Delivers a finish-ready surface - the checkered full round head accepts stains, paints, and surface finishes, so exposed nailheads blend into decking and siding instead of standing out as shiny spots.
• Backed by code-recognized standards - these stainless steel nails are recommended for permanent wood foundation construction per ANSI/AF&PA specifications, supporting builders who need fasteners that meet defined performance criteria on permitted projects.

Specifications

• Brand: Simpson Strong-Tie
• Coating/Material: Type 316 Stainless Steel
• Penny Size: 8d
• Length: 2-1/2 in.
• Head Diameter: 1/4 in.
• Shank Diameter: 0.113 in.
• Gauge: 12
• Shank Type: Annular-Ring Shank
• Head Type: Full Round Head
• Head Pattern: Checkered
• Point Type: Diamond Point
• Approx. Count per Lb.: 138
• Country of Origin: United States

Available Pack Options

• T8ABN1: 1 Lb (138)
• T8ABN5: 5 Lb (690)
• T8ABNB: 25 Lb (3450)

Frequently Asked Questions

What is the difference between Type 316 and Type 304 stainless steel for nails?

Type 316 stainless steel contains added molybdenum, which gives it superior resistance to chlorides, salt spray, and corrosive chemicals compared to Type 304. Simpson specifically recommends Type 316 for seaside applications and any environment where maximum corrosion resistance is required. Type 304 is suitable for general outdoor use, while Type 316 is the preferred choice for coastal, marine, and salt-exposed construction.

Why does an annular ring shank nail hold better than a smooth-shank nail?

The annular ring shank features a series of rings along the shank that grip the surrounding wood fibers as the nail is driven. This mechanical interlock dramatically increases withdrawal resistance - meaning the nail resists being pulled back out under load - compared to a smooth shank, which relies only on friction. This makes annular ring shank nails especially valuable in decking, siding, and structural assemblies subject to repeated stress or seasonal movement.

Are these nails approved for permanent wood foundation construction?

Yes. Stainless steel nails of this type are recommended for the construction of permanent wood foundations per the ANSI/AF&PA Permanent Wood Foundations Design Specifications. Always verify current local building codes and project specifications with a qualified professional to confirm fastener requirements for your specific application.

What does the checkered head pattern offer beyond appearance?

The checkered pattern on the full round head serves three practical purposes: it blends with natural wood grain for a less conspicuous appearance, it reduces glare from sunlight on exposed decking and siding, and it accepts surface finishes such as stains and paints so the nailhead can be finished to match the surrounding material.

Note: Product dimensions may differ from picture. Please see item description for specifications.