ISO7380 Button Head SEMS Screws

FULLERKREG ISO7380 Button Head SEMS Screws are a tri-combination captive fastener assembly consisting of an ISO7380 low-profile button head cap screw with a pre-assembled flat washer (GB/T 9074.24) and spring washer (GB/T 9074.26). The domed button head provides a clean, flush appearance; the captive dual-washer stack delivers broad load distribution and vibration-resistant retention — all in one inseparable unit. Available in A2 stainless steel and high-strength alloy steel Class 10.9 black oxide.

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ISO7380 Button Head SEMS Screw Series

ISO7380 Button Head SEMS Screws — Stainless Steel A2 (SUS304)
Material: A2 Stainless Steel (SUS304)  ·  Finish: Passivated  ·  Grade: A2-70  ·  Washers: GB9074.24 + GB9074.26  ·  Range: M3–M10

ISO7380 Button Head SEMS Screws — Alloy Steel Class 10.9, Black Oxide
Material: Alloy Steel 10B21  ·  Finish: Black Oxide  ·  Grade: Class 10.9  ·  Washers: GB9074.24 + GB9074.26  ·  Range: M3–M10

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Selection Guide

Series	Material	Finish	Grade	Tensile Strength	Best For
A2 Stainless Steel	SUS304 (18-8)	Passivated	A2-70	≥ 700 MPa	Corrosion resistance, electronics, appliances, visible surfaces
Alloy Steel 10.9 Black	Alloy Steel 10B21	Black Oxide	Class 10.9	≥ 1040 MPa	High-strength joints, automotive, machinery, robotics, black aesthetics

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What Is an ISO7380 Button Head SEMS Screw?

ISO7380 Button Head SEMS Screws combine three components into one inseparable assembly:

Component	Standard	Role
① ISO7380 Button Head Cap Screw	ISO 7380 / ISO 7380.3	Low-profile domed head with hex socket (Allen) drive; provides clamping force
② Flat Washer	GB/T 9074.24	Distributes clamping load; protects substrate surface from indentation
③ Spring Washer (Split Lock Washer)	GB/T 9074.26	Elastic preload resists self-loosening under vibration and dynamic loads

Assembly order from screw head to workpiece: Head → Spring Washer (GB9074.26) → Flat Washer (GB9074.24) → Workpiece. Both washers rotate freely on the shank but cannot be removed after assembly.

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Product Images

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Why FULLERKREG?

🏭 Direct Manufacturer — Full in-house production from wire drawing to finished tri-combination assembly
📐 Strict Dimensional Control — 100% inspection against ISO 7380, GB/T 9074.24 & GB/T 9074.26
📦 Flexible MOQ — Bulk packs and custom packaging available across all grades
🌍 Global Export Experience — Shipped to 40+ countries with full compliance documentation
📋 Full Traceability — Material certs, test reports, and RoHS declarations on request
⚡ Fast Lead Times — Standard sizes in stock; custom lengths within 7–15 days