Hex Head SEMS Screws

FULLERKREG hex head SEMS screws are pre-assembled fastener assemblies combining a hexagon head bolt with captivated washers — eliminating loose parts, ensuring correct washer sequence, and accelerating assembly line throughput. Available in two GB standard series across multiple materials and property classes.

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GB9074.13 — Cross Recessed Hexagon Bolt with Single Coil Lock Washer and Plain Washer Assemblies

Three-piece assembly: cross recessed (Phillips) hex bolt + plain washer (GB9074.24) + single coil spring lock washer (GB9074.26). Dual-drive design allows both screwdriver and wrench tightening. Range: M4–M10.

GB9074.13 — Stainless Steel A2 (SUS304)
Material: A2 (SUS304)  ·  Finish: Bright Passivated  ·  Class: A2-70  ·  Range: M4–M10

GB9074.13 — Marine Stainless Steel A4 (SUS316)
Material: A4 (SUS316)  ·  Finish: Bright Passivated  ·  Class: A4-70  ·  Range: M4–M10

GB9074.13 — Carbon Steel, Class 8.8, Zinc Cr3
Material: Medium Carbon Steel  ·  Finish: Zinc Cr3 (Trivalent)  ·  Class: 8.8  ·  Range: M4–M10

GB9074.13 — Low Carbon Steel, Class 4.8, Zinc Cr3
Material: Low Carbon Steel (A3/Q235)  ·  Finish: Zinc Cr3 (Trivalent)  ·  Class: 4.8  ·  Range: M4–M10

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GB9074.17 — Hexagon Bolt with Single Coil Lock Washer Assembly (Plain Hex Head, No Cross Recess)

Two-piece assembly: plain hexagon head bolt + single coil spring lock washer (GB9074.26). Wrench-drive only. Compact head profile. Range: M4–M12.

GB9074.17 — Stainless Steel A2
Material: A2 (SUS304)  ·  Finish: Bright Passivated  ·  Class: A2-70  ·  Range: M4–M12

GB9074.17 — Marine Stainless Steel A4
Material: A4 (SUS316)  ·  Finish: Bright Passivated  ·  Class: A4-70  ·  Range: M4–M12

GB9074.17 — Carbon 35K Steel, Class 8.8, Zinc Cr3
Material: 35K Carbon Steel  ·  Finish: Zinc Cr3 (Trivalent)  ·  Class: 8.8  ·  Range: M4–M12

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Selection Guide

Standard	Drive Type	Washer Config.	Material	Class	Best For
GB9074.13	Phillips + Hex Wrench	Plain + Spring Lock	A2 (SUS304)	A2-70	General corrosion resistance, indoor/outdoor
GB9074.13	Phillips + Hex Wrench	Plain + Spring Lock	A4 (SUS316)	A4-70	Marine, chemical, food-grade environments
GB9074.13	Phillips + Hex Wrench	Plain + Spring Lock	Carbon Steel	8.8	High-strength structural & automotive joints
GB9074.13	Phillips + Hex Wrench	Plain + Spring Lock	Low Carbon Steel	4.8	Light-duty, enclosures, high-volume economy
GB9074.17	Hex Wrench Only	Spring Lock Only	A2 (SUS304)	A2-70	Compact joints, corrosion-resistant environments
GB9074.17	Hex Wrench Only	Spring Lock Only	A4 (SUS316)	A4-70	Marine & chemical environments, compact profile
GB9074.17	Hex Wrench Only	Spring Lock Only	35K Carbon Steel	8.8	High-strength machinery, RoHS-compliant finish

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Product Gallery

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Why FULLERKREG Hex Head SEMS Screws?

• 🏭 Direct manufacturer — GB/T 9074.13 & GB/T 9074.17 produced in-house with full dimensional traceability
• 📦 Bulk wholesale supply — flexible MOQ across all grades and sizes; competitive OEM & MRO pricing
• 📐 Strict quality control — 100% thread gauge inspection; washer captivation verified per standard
• 📋 Full compliance documentation — mill test reports, RoHS / REACH certificates available on request
• 🌍 Global export experience — export packaging and international logistics support

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Brand: FULLERKREG   |   Standards: GB/T 9074.13-1988  ·  GB/T 9074.17   |   Materials: A2 · A4 · Steel 4.8 · Steel 8.8