Simpson #8 x 1-1/2" Flat Head 316 Stainless Steel Marine Screw from Simpson Strong-Tie is engineered specifically for boat building and marine trade applications where maximum corrosion resistance is non-negotiable. Crafted from Type 316 stainless steel - a marine-grade alloy that withstands saltwater, chemical exposure, and harsh coastal environments - this fastener drives securely into fiberglass, plywood, and wood-substitute materials. Whether you are installing trim, rub rail, or molding on a fiberglass boat hull, this flat head screw delivers a flush, professional finish combined with the long-term holding power demanding marine conditions require.

Key Features

• Type 316 Stainless Steel material - provides the ultimate in corrosion protection against saltwater, marine moisture, and chemically caustic environments, extending fastener life far beyond standard steel or zinc-plated alternatives.
• High/Low Serrated Thread design - incorporates indentations ("teeth") that cut quickly and cleanly through high-density materials like fiberglass and wood-substitute composites, reducing driving effort and improving grip.
• Extra-sharp point - speeds screw starts during assembly so you can work faster without pre-drilling in most applications.
• Flat head profile with 0.312 in. head diameter - sits flush with the surface for a clean, snag-free finish on trim, rub rail, and molding installations.
• #2 Phillips drive - compatible with standard Phillips drivers and bits, making it easy to use with tools already on hand.
• 1-1/2 in. length with 0.164 in. shank diameter - sized for secure fastening through typical boat trim and hull overlay thicknesses without over-penetrating.

Why This Product

• Designed specifically for marine and boat building trade applications, this screw solves the core challenge of fastener corrosion in saltwater and chemically aggressive environments - where standard screws fail prematurely, the Type 316 stainless steel construction holds up.
• The high/low serrated thread form was engineered for fiberglass and wood-substitute materials - the exact substrates used in boat hull construction - giving you confident, long-lasting fastener engagement where generic screws can strip or slip.
• The flush flat head profile makes this screw the right choice for applying trim, rub rail, and molding to fiberglass boat hulls, leaving a clean surface without protruding hardware that could snag lines or gear.
• From a trusted name in structural fasteners, Simpson Strong-Tie's marine screw line also comes in a pan head style, giving you compatible options for different marine fastening needs within the same product family.

Specifications

• Brand: Simpson Strong-Tie
• Screw Size: #8
• Length (in.): 1 1/2
• Material: Type 316 Stainless Steel
• Finish: Type 316 Stainless Steel
• Head Type: Flat Head
• Head Diameter (in.): 0.312
• Shank Diameter (in.): 0.164
• Drive Type: #2 Phillips
• Thread Type: High/Low Serrated Threads
• Point Type: Sharp Point
• Country of Origin: Taiwan

Available Pack Options

• T08J150FXC: 100 Pk
• T08J150FXM: 1000 Pk

Approved Applications

• Applying trim, rub rail, and molding to fiberglass boat hulls
• Fastening into fiberglass, plywood, and wood-substitute materials
• Boat building and marine trade construction
• Applications exposed to severe marine or chemically caustic conditions requiring maximum corrosion protection

Frequently Asked Questions

What materials can this marine screw fasten into?

This screw is designed to fasten securely in fiberglass, plywood, and wood-substitute materials - the primary substrates used in marine and boat building construction. The high/low serrated thread form cuts cleanly through these high-density materials for strong, reliable holding power.

Why is Type 316 stainless steel used instead of standard stainless or galvanized steel?

Type 316 stainless steel offers the ultimate in corrosion protection, making it suitable for applications exposed to saltwater, severe marine environments, and many chemically caustic conditions where standard stainless grades or galvanized coatings would degrade more quickly.

What drive tool do I need for this screw?

This screw uses a #2 Phillips drive, which is compatible with standard Phillips screwdrivers and power driver bits - tools commonly found in any marine trade or boat building workshop.

Is a flat head the only head style available for this Simpson marine screw?

No. Simpson Strong-Tie also produces these stainless-steel marine screws in a pan head style, giving you a compatible option when a raised head profile is preferred for your specific fastening application.

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