DeWALT Bi-Flex® Bi-Metal Self-Drilling Structural Screw – Phillips Pancake Head, Stalgard® GB Finish - 100/Pack

The Bi-Flex® Bi-Metal Self-Drilling Structural Screw combines the superior corrosion resistance of 300 series stainless steel with the drilling efficiency of carbon steel. Featuring a Phillips pancake head for a low-profile finish, these screws are ideal for steel-to-steel, aluminum-to-steel, aluminum-to-aluminum, and wood-to-steel connections. The Stalgard® GB coating enhances galvanic compatibility in dissimilar metal applications, including those involving aluminum. Designed for high strength, ductility, and reliability, Bi-Flex screws are immune to hydrogen-assisted stress corrosion cracking and are compatible with pressure-treated lumber.

Key Features:

• Bi-metal construction: 300 series stainless steel and carbon steel tip
• Phillips pancake head for low-profile fastening
• Stalgard® GB coating for superior galvanic corrosion resistance
• Suitable for steel, aluminum, and wood connections
• Immune to hydrogen-assisted stress corrosion cracking (HASCC)
• ICC-ES approved for code compliance in multiple building codes
• Steel-to-steel connections
• Aluminum-to-steel connections
• Aluminum-to-aluminum connections
• Wood-to-steel connections

Available Head Styles

• Phillips Undercut Flat Head (this page)
• Phillips Pan Head
• Hex Washer Head
• Phillips Flat Head with Wings
• Phillips Pancake Head

 Drill Point Types

• #2 and #3 depending on size and material thickness

Screw Sizes & Thread Options

• Diameters: #12–14 and ¼″–20
• Thread count: 14–20 TPI
• Length range: 1″ to 4″

Product: Bi-Flex® (Phillips Pancake Head) — bi-metal self-drilling structural screws

Material/Corrosion: 300-series stainless shank/head with hardened steel tapping threads & point; Stalgard® GB galvanic-barrier coating

Performance: High strength, ductility, reliability; immune to HASCC (hydrogen-assisted stress corrosion cracking) 

Suitable substrates: Steel and aluminum; compatible with pressure-treated lumber (18-8 stainless) 

Applications: Steel-to-steel, aluminum-to-steel, aluminum-to-aluminum, wood-to-steel connections 

Approvals & Listings: ICC-ES ESR-4367, ESR-4374; compliant with IBC/IRC 2012, 2015, 2018, 2021; 2020 LABC/LARC & FBC supplements; tested per AISI S905, ICC-ES AC500, AC491. 

Sizes with dimensions & box weights

• DFSEBN300 — #10-16 × 1" (Pancake, #2 point)
  Nominal head Ø: 0.435"  |  Head height: 0.075"  |  Max load-bearing length: 0.500"  |  Min protrusion: 1/2"  |  Finish: Stalgard® GB  | Full Case qty 4,000
• DFSEBN320 — #12-14 × 1" (Pancake, #3 point)
  Nominal head Ø: 0.435"  |  Head height: 0.075"  |  Max load-bearing length: 0.406"  |  Min protrusion: 19/32" (≈0.594")  |  Finish: Stalgard® GB  |  Full Case qty 4,000 

Q: What does the Stalgard® GB finish do?
A: Stalgard® GB is a corrosion-resistant coating formulated to improve galvanic compatibility when joining dissimilar metals (e.g., aluminum to steel), helping reduce staining and corrosion at the connection.

Q: What are these screws typically used for?
A: They’re self-drilling structural fasteners with a low-profile pancake head, commonly used for attaching panels, trim, and components in metal construction where a flush, wide-bearing head is preferred.

Q: Do I need to pre-drill?
A: In most light-gauge metal applications, no pre-drilling is required—the self-drilling point is designed to drill and tap in one step. For thicker substrates, follow the manufacturer’s thickness/point guidance and test first.

Q: Is this screw suitable for aluminum-to-steel attachments?
A: Yes. The GB (galvanic barrier) coating is designed to help when fastening aluminum to steel by reducing galvanic reaction at the interface. Ensure proper isolation and sealing per your specification for best results.

Q: How are these packaged?
A: This item is sold as a 100-pack. Refer to the size selector on the page for available diameters and lengths.