Simpson #8 x 1" Self-Drilling Hex-Washer Head Screw in 316 Stainless Steel is a precision-engineered fastener from Simpson designed for reliable performance in demanding environments. Built from Type 316 stainless steel, this screw delivers exceptional resistance to corrosion, moisture, and harsh outdoor conditions - making it a trusted choice for aluminum and fiberglass fastening applications. The self-drilling tip eliminates the need for a pilot hole, streamlining installation and saving time on the job. Sold individually, this hex-washer head screw is a go-to solution for contractors and builders who need a dependable stainless steel fastener for non-steel substrates.

Key Features

• Type 316 Stainless Steel construction - provides superior corrosion resistance in wet, marine, and chemically exposed environments, outlasting standard zinc or coated fasteners in harsh conditions
• Self-drilling #3 drill point - cuts its own pilot hole during installation, reducing prep work and speeding up fastening in aluminum and fiberglass materials
• Indented hex-washer head with 1/4 in. hex drive - delivers a secure grip surface that distributes load across a wider bearing area, reducing the risk of pull-through and providing a clean, professional finish
• Tapping screw thread at 18 TPI - forms its own mating thread in the material for a tight, vibration-resistant hold without pre-tapping
• #8 screw size at 1 inch length - a compact, versatile profile suited to thin-material fastening in aluminum panels, fiberglass sheets, and similar non-steel assemblies

Why This Product

• 316 stainless steel is the material of choice for corrosion-prone settings - this screw stands up to saltwater exposure, chemical environments, and prolonged outdoor use where lesser materials would degrade
• The self-drilling tip combined with tapping threads means faster installation with fewer tools - no pre-drilling or pre-tapping required in aluminum and fiberglass applications
• The indented hex-washer head style provides both a wide bearing surface and positive driver engagement, reducing cam-out and helping maintain a secure, flush installation
• Specifically engineered for aluminum and fiberglass fastening - not for steel - ensuring you get the right fastener geometry and tip design for non-ferrous and composite materials

Specifications

• Brand: Simpson Strong-Tie
• MPN: T08100HDUC
• Screw Size: #8
• Length: 1 in.
• Material: Type 316 Stainless Steel
• Head Type: Indented Hex Washer Head
• Drive Type: 1/4 in. Hex
• Thread Type: Tapping Threads
• TPI: 18
• Point Type: #3 Drill Point
• Country of Origin: Taiwan

Approved Applications

• Fastening aluminum materials
• Fastening fiberglass materials
• Not intended for use in steel

Frequently Asked Questions

Can this screw be used to fasten steel?

No. This self-drilling hex-washer head screw is designed specifically for fastening aluminum and fiberglass. It is not intended for use in steel applications. Using the correct fastener for your substrate ensures a secure hold and preserves the integrity of the drill point.

What drive tool is required to install this screw?

This screw uses a 1/4 in. hex drive, so a standard 1/4 in. hex bit or nut driver is required for installation. The indented hex-washer head provides positive engagement with the driver, helping to minimize slipping during fastening.

Why choose 316 stainless steel over other stainless grades for this type of application?

Type 316 stainless steel contains added molybdenum compared to 304 stainless, which enhances its resistance to chlorides, saltwater, and chemical exposure. This makes it particularly well-suited for coastal, marine, and outdoor environments where long-term corrosion resistance is critical.

Does this screw require a pilot hole before installation?

No. The #3 drill point is a self-drilling tip that creates its own pilot hole as the screw is driven, eliminating the need for pre-drilling in aluminum and fiberglass. The tapping threads then form a secure mating thread in the material as the screw advances.

Note: Product dimensions and/or thread length may differ from picture. Please see the item description above for specifications.