What is a Bi-Flex® Self-Drilling Screw?

Bi-Flex® self-drilling screws are high-performance fasteners designed for attaching metal components. They feature a #1 drill point tip for quick starts, and a Stalgard® coating that resists corrosion and rust over time.

What makes Bi-Flex® screws ideal for metal-to-metal applications?

The Bi-Flex® screws include a self-drilling point that eliminates the need for pre-drilling, combined with a hex washer head for better torque control, making them perfect for metal-to-metal connections.

Why choose Bi-Flex® over other fasteners?

Bi-Flex® screws outperform standard fasteners with faster penetration, superior corrosion protection from Stalgard®, and consistent structural performance, even in demanding environments.

Are Bi-Flex® screws compatible with impact drivers?

Yes, Bi-Flex® screws feature a 1/4” hex drive that works with standard drills and impact drivers for quick, secure installation.

What head style do Bi-Flex® screws have?

They feature a hex washer head, which offers a broader bearing surface and helps prevent over-driving or stripping.

What coating is used on Bi-Flex® screws?

Each screw is coated with Stalgard®, a high-performance, multi-layer anti-corrosion finish engineered for long-term outdoor durability.

How many Bi-Flex® screws come in a pack?

Each item is sold in contractor-ready 100 packs, making them ideal for large projects and repeated use.

Can Bi-Flex® screws be used in structural applications?

Yes, they meet or exceed industry standards for structural performance, including ASTM and SAE specs, making them suitable for commercial and structural applications.

Are these screws resistant to rust and corrosion?

Absolutely. The advanced Stalgard® coating resists red rust and corrosion even in coastal and high-humidity environments.

Where can I get help choosing the right size screw?

Call us at 800.859.4077 — our expert team will help you select the right Bi-Flex® size and type for your specific job.

DeWalt Bi-Flex® Self-Drilling Metal Screws – Hex Washer Head | Stalgard® Coated Fasteners for Metal-to-Metal Applications, 100/Packs

Need Help? Call Us: 800-859-4077

#1 Drill Point Tip — Fast, precise starts that won’t walk or clog
Zinc-Plated with Stalgard® Coating — Built to resist corrosion, rust, and harsh weather
High Thread Engagement — Locks tight for strong pull-out resistance
Hex Washer Head — Clean finish and strong drive control with standard hex tools
Sold in 100 Packs — Bulk quantity for pros, priced for savings
Multiple Length Options — Ideal for HVAC, steel framing, purlins, cladding, and more
Tested for Structural Reliability — Meets ASTM A510 & SAE J78 standard
Expert support just a call away – 800.859.4077

Item #DEW-AJ

Item #	Description	Price
DEW-DFSEAJ110	#10-16 X 3/4" \| Nominal Head Diameter: 0.4" \| Nominal Head Height: 0.16" \| Point Type: #2 \| Max Load Bearing Length: 0.25" \| Min Protrusion Length: 1/2" \| Box/100	$49.00
DEW-DFSEAJ120	#10 x 1" \| Nominal Head Diameter: 0.4" \| Nominal Head Height: 0.16" \| Point Type: #2 \| Max Load Bearing Length: 0.5" \| Min Protrusion Length: 1/2" \| Box/100	$54.00
DEW-DFSEAJ140	#10-16 X 1-1/2" \| Nominal Head Diameter: 0.4" \| Nominal Head Height: 0.16" \| Point Type: #2 \| Max Load Bearing Length: 1" \| Min Protrusion Length: 1/2" \| Box/100	$56.00
DEW-DFSEAJ185	#12 - 14 x 1" \| Nominal Head Diameter: 0.415" \| Nominal Head Height: 0.2" \| Point Type: #2 \| Max Load Bearing Length: 0.406" \| Min Protrusion Length: 19/32" \| Box/100	$60.00
DEW-DFSEAJ190	#12 - 14 x 1" \| Nominal Head Diameter: 0.415" \| Nominal Head Height: 0.2" \| Point Type: #3 \| Max Load Bearing Length: 0.406" \| Min Protrusion Length: 19/32" \| Box/100	$64.00
DEW-DFSEAJ215	#12 - 14 x 1-1/2" \| Nominal Head Diameter: 0.415" \| Nominal Head Height: 0.2" \| Point Type: #2 \| Max Load Bearing Length: 0.906" \| Min Protrusion Length: 19/32" \| Box/100	$76.00
DEW-DFSEAJ220	#12 - 14 x 1-1/2" \| Nominal Head Diameter: 0.415" \| Nominal Head Height: 0.2" \| Point Type: #3 \| Max Load Bearing Length: 0.906" \| Min Protrusion Length: 19/32"3 \| Box/100	$82.00
DEW-DFSEAJ240	#12 - 14 x 2" \| Nominal Head Diameter: 0.415" \| Nominal Head Height: 0.2" \| Point Type: #2 \| Max Load Bearing Length: 1.406" \| Min Protrusion Length: 19/32" \| Box/100	$95.00
DEW-DFSEAJ260	#12 - 14 x 2-1/2" \| Nominal Head Diameter: 0.415" \| Nominal Head Height: 0.2" \| Point Type: #3 \| Max Load Bearing Length: 1.906" \| Min Protrusion Length: 19/32 \| Box/100	$134.00
DEW-DFSEAJ320	#12 - 24 x 1-1/2" \| Nominal Head Diameter: 0.415" \| Nominal Head Height: 0.2" \| Point Type: #5 \| Max Load Bearing Length: 0.5" \| Min Protrusion Length: 1" \| Box/100	$84.00
DEW-DFSEAJ340	#12 - 24 x 2" \| Nominal Head Diameter: 0.415" \| Nominal Head Height: 0.2" \| Point Type: #5 \| Max Load Bearing Length: 1" \| Min Protrusion Length: 1" \| Box/100	$96.00
DEW-DFSEAJ415	1/4" - 14 x 1" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #2 \| Max Load Bearing Length: 0.406" \| Min Protrusion Length: 19/32" \| Box/100	$88.00
DEW-DFSEAJ430	1/4" - 14 x 1-1/2" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #2 \| Max Load Bearing Length: 0.906" \| Min Protrusion Length: 19/32" \| Box/100	$107.00
DEW-DFSEAJ445	1/4" - 14 x 2" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #2 \| Max Load Bearing Length: 1.406" \| Min Protrusion Length: 19/32" \| Box/100	$123.00
DEW-DFSEAJ540	1/4" - 20 x 1" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #3 \| Max Load Bearing Length: 0.406" \| Min Protrusion Length: 19/32" \| Box/100	$89.00
DEW-DFSEAJ580	1/4" - 20 x 1-1/2" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #3 \| Max Load Bearing Length: 0.906" \| Min Protrusion Length: 19/32" \| Box/100	$125.00
DEW-DFSEAJ600	1/4" - 20 x 1-1/2" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #5 \| Max Load Bearing Length: 0.5" \| Min Protrusion Length: 1" \| Box/100	$143.00
DEW-DFSEAJ610	1/4" - 20 x 2" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #3 \| Max Load Bearing Length: 1.406" \| Min Protrusion Length: 19/32" \| Box/100	$149.00
DEW-DFSEAJ615	1/4" - 20 x 2" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #5 \| Max Load Bearing Length: 1" \| Min Protrusion Length: 1" \| Box/100	$160.00
DEW-DFSEAJ630	1/4" - 20 x 3" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #5 \| Max Load Bearing Length: 2" \| Min Protrusion Length: 1" \| Box/100	$223.00
DEW-DFSEAJ640	1/4" - 20 x 2-1/2" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #3 \| Max Load Bearing Length: 1.906" \| Min Protrusion Length: 19/32" \| Box/100	$185.00
DEW-DFSEAJ650	1/4" - 20 x 3" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #3 \| Max Load Bearing Length: 2.406" \| Min Protrusion Length: 19/32" \| Box/100	$213.00
DEW-DFSEAJ660	1/4" - 20 x 4" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #3 \| Max Load Bearing Length: 3.406" \| Min Protrusion Length: 19/32" \| Box/100	$270.00
DEW-DFSEAJ675	1/4" - 20 x 5" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #5 \| Max Load Bearing Length: 4" \| Min Protrusion Length: 1" \| Box/50	$192.00
DEW-DFSEAJ680	1/4" - 20 x 6" \| Nominal Head Diameter: 0.5" \| Nominal Head Height: 0.25" \| Point Type: #5 \| Max Load Bearing Length: 5" \| Min Protrusion Length: 1" \| Box/50	$225.00

Description

DeWalt Bi-Flex® Self-Drilling Metal Screws are engineered for reliable, high-performance fastening in metal-to-metal applications. Whether you're installing steel framing, metal roofing panels, or structural decking, these hex washer head screws deliver consistent drive, secure holding power, and long-lasting durability.

Manufactured with precision-formed drill points (#2, #3, and #5), DeWalt Bi-Flex® fasteners eliminate the need for pre-drilling—saving time on job sites. Each screw is coated with Stalgard® GB, a premium corrosion-resistant finish tested to withstand extreme weather and jobsite conditions.

Available in a range of sizes and point types, these self-drilling screws are the go-to solution for professionals demanding reliability, speed, and strength.

Key Features:

Hex Washer Head Design – Distributes load evenly for added holding power
Self-Drilling Points – Available in #2, #3, and #5 types for varying steel thickness
Stalgard® GB Finish – Industry-trusted multilayer coating for corrosion resistance
High-Torque Carbon Steel – Designed for structural strength and drive consistency
No Pre-Drilling Required – Installs fast through light and heavy-gauge steel
Packaged in 100 Packs – Simplifies ordering and replenishment for contractors
Backed by DeWalt Quality – Trusted name in construction fastening

Applications

Steel-to-Steel Connections
Aluminum-to-Steel / Aluminum-to-Aluminum Fastening
Roofing Panels, Framing, HVAC & Duct Installations
Commercial Construction
Solar & Renewable Installations

Available Head Styles

Hex Washer Head
Phillips Pan Head
Phillips Flat Head
Phillips Undercut Flat Head
Phillips Pancake Head

Drill Point Types

#2, #3, #5 – depending on size
Wings for wood-to-metal where applicable

Screw Sizes & Thread Options

#8 to 1/4" Diameter
Thread count: 14–24 TPI
Length: 3/4" to 8"

Specifications

Type / Material: Bi-metal self-drilling/tapping structural screws — 300-series stainless body with hardened drilling tip

Corrosion protection: Stalgard® GB coating for enhanced galvanic compatibility (great for dissimilar metals incl. aluminum)

Performance: High strength, ductility, and reliability; immune to HASCC (vs. case-hardened fasteners)

Head / Drive: Hex Washer Head; typical drives — 5/16″ for #10/#12, 3/8″ for 1/4″

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

Approvals (family): ICC-ES ESR-4367, ESR-4374; tested per AISI S905, AC500 (misc. to steel), AC491 (aluminum)

Dimensions (by diameter)

#10: head Ø 0.400″, head height 0.160″
#12: head Ø 0.415″, head height 0.200″
1/4″: head Ø 0.500″, head height 0.250″

Representative size details (length • point • load-bearing / protrusion • pack)

DFSEAJ110 — #10-16 × 3/4″: #2 • Max LB 0.25″ / Min Protrusion 1/2″ • 5,000/box
DFSEAJ120 — #10-16 × 1″: #2 • 0.50″ / 1/2″ • Full Case qty 5,000/box
DFSEAJ140 — #10-16 × 1-1/2″: #2 • 1.00″ / 1/2″ • Full Case qty 2,500/box
DFSEAJ185 — #12-14 × 1″: #2 • 0.406″ / 19/32″ • Full Case qty 3,000/box
DFSEAJ240 — #12-14 × 2″: #2 • 1.406″ / 19/32″ • Full Case qty 1,500/box
DFSEAJ260 — #12-14 × 2-1/2″: #3 • 1.906″ / 19/32″ • Full Case qty 1,000/box
DFSEAJ540 — 1/4″-20 × 1″: #3 • 0.406″ / 19/32″ • Full Case qty 2,500/box
DFSEAJ615 — 1/4″-20 × 2″: #5 • 1.00″ / 1.00″ • Full Case qty 1,500/box
DFSEAJ650 — 1/4″-20 × 3″: #3 • 2.406″ / 19/32″ • Full Case qty 500/box
DFSEAJ670 — 1/4″-20 × 4″: #5 • 3.000″ / 1.00″ • Full Case qty 500/box
DFSEAJ675 — 1/4″-20 × 5″: #5 • 4.000″ / 1.00″ • Full Case qty 250/box
DFSEAJ680 — 1/4″-20 × 6″: #5 • 5.000″ / 1.00″ • Full Case qty 250/box

Typical carton weight ranges*

#10 (5,000/box): ~35–45 lb depending on length
#12 (1,000–4,000/box): ~30–50 lb depending on length/pack
1/4″ (250–2,500/box): ~25–55 lb depending on length/pack
*Weights vary by supplier and packaging (bulk vs. boxed). If you want exact shipping weights per SKU, say the word and I’ll pull verified numbers.

FAQs

Q: What materials can Bi-Flex® screws fasten?
A: Bi-Flex® screws are ideal for fastening steel and aluminum in both light- and heavy-gauge metal applications. They’re commonly used in commercial roofing, HVAC, and framing projects.

Q: What is the Stalgard® coating on these screws?
A: Stalgard® is a high-performance, multilayer coating system designed to resist corrosion, even in extreme environments. It extends the lifespan of each fastener by protecting it from rust, chemicals, and wear.

Q: Which Bi-Flex® screw size is right for my project?
A: That depends on your material thickness and fastening needs. We offer a wide range of Bi-Flex® screw sizes to cover most metal-to-metal applications. Still unsure? Give us a call at 800.859.4077 — our team will help you choose the perfect fit.

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