Simpson Strong-Drive HCKMTH114S MTH Wood Underlayment Screw (Collated) - #7 x 1-1/4 in., Gray Phosphate (1,000-Pack) is engineered by Simpson Strong-Tie for fast and secure underlayment-to-subfloor installations. Unlike nails, the MTH Underlayment screw features an intricate high-low thread pattern designed to prevent squeaking by holding underlayment tight to the subfloor and preventing pull-out. Its compact trim head allows for a flush surface and prevents floor coverings from settling in countersink recesses.

Key Features

• Trim head with nibs for easy countersinking
• #2 square drive for reliable torque transfer
• Driver bit included in each box (replacement bit model BIT2S)
• High-low threads designed to resist pull-out and prevent subfloor squeaking
• Sharp point for clean, fast penetration
• Curved collation for use with compatible auto-feed driving systems
• Gray phosphate coating recommended for dry, low-corrosion environments
• Quantity: 1,000 screws per pack

Specifications

• Model Number (MPN): HCKMTH114S
• Screw Size: #7
• Length: 1-1/4 in.
• Head Type: Trim Head
• Drive Type: #2 Square
• Thread Type: High/Low Threads
• Point Type: Sharp Point
• Collation Type: Curved
• Coating: Gray Phosphate Coating
• Compatible Tool: Simpson Strong-Tie Quik Drive PRO200SG2 auto-feed screw driving system or attachment
• Quantity: 1,000
• Country of Origin: Taiwan

Approved Applications

• Underlayment / Backer board installation to subfloor

What's Included

• #2 square drive bit (model BIT2S)

Frequently Asked Questions

What makes the MTH Underlayment screw better than nails for subfloor applications?

Unlike nails, the MTH Underlayment screw features an intricate high-low thread pattern specifically designed to prevent squeaking by holding underlayment tight to the subfloor and preventing pull-out, providing a more secure and long-lasting connection.

What tool is required to install these collated underlayment screws?

These screws install with the Simpson Strong-Tie Quik Drive PRO200SG2 auto-feed screw driving system or attachment, which is compatible with the curved collation strip format of these screws.

Are these screws suitable for wet or high-moisture environments?

No. The gray phosphate coating is recommended for dry, low-corrosion environments only. For installations in areas with higher moisture exposure, a different corrosion-resistant coating would be more appropriate.

Does this pack include a driver bit?

Yes. Each box includes a #2 square drive bit (model BIT2S) so you can get started right away. Replacement bits are available separately under model number BIT2S.

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