Simpson 8d Premium Siding Nail in passivated Type 316 Stainless Steel is engineered for demanding exterior fastening applications where standard nails fall short. Designed by Simpson Strong-Tie, this 2-1/2" nail delivers reliable, corrosion-resistant performance in severely corrosive environments - including coastal and seaside installations where saltwater exposure is a daily reality. Whether you are securing wood siding on a beachfront home or a high-moisture exterior wall, this fastener is built to hold firm and resist degradation over the long term.

Key Features

• Passivated Type 316 Stainless Steel material - provides exceptional resistance to saltwater, harsh chemicals, and severe outdoor exposure, making this nail ideal for coastal and high-humidity environments where inferior fasteners would corrode and fail
• Annular-Ring Shank design - the ringed shank bites into wood fibers as it drives, dramatically increasing withdrawal resistance and holding power compared to smooth-shank nails, so your siding stays securely fastened over time
• Full Round Head with Circle Head pattern - the circle-patterned head minimizes glare on exterior surfaces and accepts paint or other surface finishes cleanly, helping installed siding look professional and polished
• Diamond Point tip - drives straight and true while reducing the risk of splitting boards during installation, saving time and reducing material waste on the job site
• 13 Gauge wire at 0.092" shank diameter - sized appropriately for exterior siding applications, offering a balance of strength and compatibility with standard siding nail guns and hand-driving
• 2-1/2" length (8d penny size) - provides the penetration depth needed to fasten wood siding securely to sheathing and framing members
• Made in the United States - manufactured domestically to consistent quality standards

Why This Product

• Purpose-built for severely corrosive environments - standard galvanized fasteners can corrode and stain siding in coastal or high-salt-air locations. The passivated 316 stainless steel construction of this nail resists exactly those conditions, protecting both the fastener and the surrounding siding material.
• Stronger grip than smooth-shank alternatives - the annular-ring shank provides significantly greater withdrawal resistance than smooth nails, meaning siding is less likely to loosen, pull away, or buckle over years of seasonal movement and wind loading.
• Reduces splitting risk on finish siding - the diamond point tip is designed to drive true and minimize board splitting, which is especially important when working with narrow or fragile exterior siding boards where cracking would require costly replacement.
• Finish-friendly head design - the circle-pattern full round head is engineered to accept surface finishes, so painted or stained siding applications maintain a clean, uniform appearance without unsightly glare or uneven texture at the nail head.

Specifications

• Brand: Simpson Strong-Tie
• Material: Type 316 Stainless Steel
• Finish: Type 316 Stainless Steel
• Penny Size: 8d
• Length: 2-1/2 in.
• Gauge: 13
• Shank Diameter: 0.092 in.
• Head Diameter: 5/32 in.
• Shank Type: Annular-Ring Shank
• Head Type: Full Round Head
• Head Pattern: Circle Head
• Point Type: Diamond Point
• Approx. Count per Lb.: 196
• Country of Origin: United States

Available Pack Options

• T8KR51: 1 Lb (196)
• T8KR55: 5 Lb (980)
• T8KR5B: 25 Lb (4900)

Approved Applications

• Fastening Wood Siding

Frequently Asked Questions

Why is Type 316 stainless steel recommended for siding near the coast?

Type 316 stainless steel contains molybdenum, which gives it superior resistance to chlorides - such as salt air and seawater - compared to standard 304 stainless or galvanized steel. This nail is also passivated, a surface treatment that further enhances its corrosion resistance. These properties make it the appropriate choice for siding in seaside and other severely corrosive environments where other fastener materials would degrade prematurely.

What does the annular-ring shank do, and why does it matter for siding applications?

The annular-ring shank features ridges along its length that engage wood fibers as the nail is driven. This dramatically increases withdrawal resistance - meaning the nail is far harder to pull back out than a smooth-shank nail of the same size. For exterior siding that endures wind loads, thermal expansion, and contraction over years of use, greater holding power helps keep the siding flat, secure, and free from loosening or gaps.

What does "passivated" mean, and how does it improve this nail's performance?

Passivation is a chemical surface treatment applied to stainless steel that removes free iron and other surface contaminants, leaving a clean oxide layer that enhances corrosion resistance. On this siding nail, passivation ensures the 316 stainless steel surface performs at its full corrosion-resistant potential - particularly important in environments with salt spray, moisture, or chemical exposure.

Will the circle-pattern head accept paint or stain without standing out on finished siding?

Yes. The circle-pattern head on this nail is specifically designed to reduce glare and accept surface finishes such as paint or stain. This makes it well-suited for applications where the finished appearance of the siding matters, allowing the nail heads to blend into the painted or stained surface rather than reflecting light or creating an uneven look.

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