The Simpson Strong-Tie Strong-Drive SDHR Combo-Head Screw - 12 mm x 160 mm in Black E-Coat is a heavy-duty structural fastener engineered for cross-laminated timber (CLT), mass timber construction, and general interior wood applications. Featuring a distinctive combination head that accepts either a 17 mm hex-head driver bit or a T40 6-lobe driver bit, this partially-threaded screw delivers exceptional connection strength - particularly when fastening steel plate or angle connectors to wood. The black e-coat electrocoating finish provides a durable, nonmetallic, friction-reducing barrier suited to dry-service interior environments, while the robust knurled shank and Type-17 point make it self-drilling in most wood assemblies without the need for predrilling.

Key Features

• Black e-coat electrocoating finish - provides a construction-durable, nonmetallic and friction-reducing coating that resists corrosion in interior dry-service conditions, keeping connections secure over time without the bulk of metallic coatings
• Optimized hardness profile - helps mitigate field embrittlement issues and is compliant with CSA O86:24 hydrogen embrittlement requirements, giving installers confidence in structural reliability under demanding conditions
• Combination head accepts T40 6-lobe or 17 mm hex-head driver bit - gives crews flexibility to use whichever tool is on hand, reducing downtime and driver bit changes on the job site
• Heavy-duty shank with robust knurl - reduces installation torque so structural screws can be driven with less effort, improving speed and reducing tool wear during large-scale timber framing or CLT assembly
• Type-17 point - ensures fast starts, reduces installation torque, and eliminates the need for predrilling in most applications, cutting labor time on mass timber and engineered wood projects
• Designed for use with steel side plates - allows direct steel-to-wood and steel-to-engineered-wood connections, broadening application versatility for structural assemblies and modular construction
• Partially threaded shank - concentrates clamping force at the connection point to provide excellent pull-through and shear resistance where it matters most
• 160 mm (6-1/4 in.) length with 4-3/8 in. thread length - sized for thick timber members and deep steel plate connections common in CLT and mass timber construction

Why This Product

• Purpose-built for mass timber and CLT construction - the SDHR Combo-Head screw is specifically designed for cross-laminated timber, mass timber, and engineered wood assemblies where standard fasteners fall short in connection strength and depth penetration
• Eliminates predrilling in most applications - the Type-17 point self-drills into wood, saving significant labor time on projects where hundreds or thousands of structural fasteners must be driven
• Dual-drive head reduces tool dependency - the combination head works with both a T40 6-lobe bit and a 17 mm hex-head driver, so installation can continue regardless of which driver is available on the job site
• Meets modern embrittlement standards - compliance with CSA O86:24 hydrogen embrittlement requirements means the SDHR is engineered to maintain its structural integrity in the field, not just in the lab

Specifications

• Brand: Simpson Strong-Tie
• Product Name: Strong-Drive SDHR COMBO-HEAD Screw
• Diameter (Nominal): 12 mm
• Length: 160 mm (6-1/4 in.)
• Thread Length: 4-3/8 in.
• Shank Diameter: 0.315 in.
• Head Diameter: 0.669 in.
• Head Type: Combination
• Drive Type: T40 6-Lobe or Hex-Head
• Point Type: Type-17 Point
• Coating: E-coat Electrocoating
• Finish: E-coat Electrocoating
• Color: Black