The Simpson CB3BLGHL Fiber-Cement Board Screw is a collated fastener engineered specifically for cement-board-to-wood applications in coarse, porous, and softer materials. Designed to work with the Quik Drive PROLDHG2 underlayment/backerboard system, this #9 x 1-5/8 in. screw combines alternating high-low threads with a sharp point to drive cleanly and seat flush - delivering a concealed, professional finish on every backer board and fiber-cement installation.

Key Features

• 0.375-in. ribbed wafer head with nibs - allows the screw to countersink smoothly and consistently, leaving a clean, flush surface ready for finishing without extra prep work
• #3 undersized square drive - reduces cam-out and keeps the bit engaged through the full drive cycle; 2 driver bits are included in every box (replacement bit model BIT3SU)
• Alternating high-low threads at 15 TPI - the high-low thread pattern bites aggressively into coarse and porous substrates while reducing driving torque, making installation faster and less fatiguing
• Sharp point - starts without pre-drilling, piercing fiber-cement board and wood backing cleanly for efficient, uninterrupted collated fastening
• C-3 mechanically galvanized coating - provides corrosion resistance suited to the alkaline environment of cement board installation, helping fasteners hold long-term
• Straight collation - compatible with the Quik Drive PROLDHG2 system for continuous, high-volume fastening that keeps large flooring and backerboard jobs moving
• 1,500-count packaging - provides enough collated screws to cover substantial square footage without frequent reordering mid-job

Why This Product

• Purpose-built for fiber-cement and backer board work - unlike general-purpose screws, the CB3BLGHL is specifically engineered for cement-board-to-wood applications in coarse, porous, and softer materials, meaning the thread geometry, head profile, and point type are all optimized for this exact task
• System-matched for the Quik Drive PROLDHG2 - straight collation and screw geometry are designed to run reliably through this auto-feed underlayment and backerboard tool, reducing jams and keeping installation pace high on larger projects
• Countersinking without extra steps - the ribbed wafer head with nibs seats the screw flush in one motion, eliminating the need to manually set depth or sand down proud fastener heads before tiling or finishing
• Corrosion-resistant coating for demanding substrates - the C-3 mechanically galvanized finish holds up in the alkaline, moisture-prone environment around cement board, making these screws a dependable long-term choice for wet-area and underlayment applications

Specifications

• Model No.: CB3BLGHL158S
• Screw Size: #9
• Length: 1-5/8 in.
• Head Type: Ribbed Wafer Head
• Head Diameter: 0.383 in.
• Drive Type: #3 Square, Undersized
• Thread Type: High/Low Threads
• TPI: 15
• Point Type: Sharp Point
• Collation Type: Straight
• Collation Angle: Straight
• Coating/Finish: Mechanically Galvanized, C-3
• Compatible Tool: Quik Drive PROLDHG2
• Packaging Quantity: 1,500

Approved Applications

• Cement board to wood (for coarse, porous, and softer materials)
• Fastening Wood-to-Steel

What's Included

• 1,500 collated #9 x 1-5/8 in. CB3BLGHL fiber-cement board screws
• 2 driver bits included (replacement bit model BIT3SU)

Frequently Asked Questions

What application is the CB3BLGHL158S screw designed for?

This screw is designed for cement-board-to-wood applications, specifically in coarse, porous, and softer materials. It is intended for use with the Quik Drive PROLDHG2 underlayment/backerboard system.

What type of drive does this screw use, and are driver bits included?

The CB3BLGHL158S uses a #3 undersized square drive. Each box includes 2 driver bits. If replacement bits are needed, the compatible model is BIT3SU.

What coating does this screw have, and why does it matter?

This screw features a C-3 mechanically galvanized coating, which provides corrosion resistance suited for cement board installation environments.

How does the ribbed wafer head design benefit installation?

The 0.375-in. ribbed wafer head includes nibs that allow the screw to countersink easily into the material, producing a clean, concealed finish for a professional result.

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