Product Summary

Longze Torx Drive Countersunk Head Self-Tapping Screws are high-performance fasteners manufactured according to ISO 14586 Und DIN 7982 standards, widely used in automotive assembly, window & door

installation, cabinetry, and sheet metal fabrication. Featuring a flat countersunk head with a 6-lobe Torx drive, these Longze Torx Drive Countersunk Head Self-Tapping Screws are designed to cut their own

threads into pre-drilled holes in metal or plastic, providing a flush, high-torque finish that resists cam-out better than traditional Phillips drives.

• ✔ High Torque Transmission: The Torx (Star) drive allows for significantly higher tightening torque without damaging the screw head or the driver bit.

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• ✔ Flush Surface Integration: The countersunk head design ensures a smooth, aerodynamic finish, making it ideal for visible exterior panels and safety-critical surfaces.

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• ✔ Self-Threading Efficiency: Precision-engineered hardened threads allow the screw to create a secure, vibration-resistant bond in various substrates.

Key Features of Torx Drive Countersunk Head Self-Tapping Screws

• Anti-Cam-Out Design – The 6-lobe drive ensures the tool stays centered, preventing the bit from slipping and scratching the workpiece.

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• Durable Sharp Points – Available in Type C (pointed) or Type F (flat end) to suit different material thicknesses and assembly needs.

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• Superior Corrosion Resistance – Offered in Zinc Plated for industrial use and Marine Grade SS316 for extreme outdoor or chemical exposure.

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• Global Standard Compliance – Fully compatible with Metric (ISO/DIN) specifications for high-precision engineering projects.

Technical Specifications

• Standards: ISO 14586 / DIN 7982 / JIS B1125

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• Metric Size Range: ST2.2 to ST9.5

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• Inch Size Range: #2 to 3/8" (Approximate equivalents)

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• Material: Case-Hardened Carbon Steel, Stainless Steel (A2 / A4)

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• Drive Type: Torx (6-Lobe / Star Drive) - T6 to T45

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• Finish: Zinc Plated (Blue/White/Yellow), Black Oxide, Dacromet, Plain

• Material & Mechanical Properties

• Material	Grad	Core Hardness	Surface Hardness	Anwendung
  Carbon Steel	Case Hardened	270 to 390 HV	$\ge 450$ HV	Sheet Metal / Automotive
  Edelstahl	SS304 (A2)	$\ge 215$ HV	N/A	Outdoor / Food Grade
  Edelstahl	SS316 (A4)	$\ge 240$ HV	N/A	Marine / Chemical / Medical

• Standard Dimensions (Metric ISO 14586)

• Size (ST)	Thread Pitch	Head Dia (dk max)	Head Height (k max)	Torx Drive No.
  ST3.5	1.3 mm	6.80 mm	2.10 mm	T10
  ST4.2	1.4 mm	8.10 mm	2.50 mm	T20
  ST4.8	1.6 mm	9.50 mm	3.00 mm	T25
  ST5.5	1.8 mm	10.80 mm	3.40 mm	T25 / T27

• Surface Treatment

• Coating	Process	Salt Spray	Anwendung
  Zinc Plated	Electroplating	72 to 144h	General Industrial / Electronics
  Black Zinc	Electroplating	48 to 96h	Stage Equipment / Automotive
  Dacromet	Zinc-Flake	1000+h	Heavy Duty / Outdoor Energy
  Passivated	Chemical	1000+h	Stainless Steel Marine Grade