M4‑0.70 x 40mm Button Socket Cap Screw – Class 10.9, Zinc‑Baked (Cr+3), ISO 7380

Designed for high‑strength metric fastening applications requiring extended length and reliable performance, this M4‑0.70 x 40mm button socket cap screw is manufactured from heat‑treated Class 10.9 alloy steel and produced to ISO 7380 standards. The 40mm length provides deep thread engagement for secure fastening through thicker or multi‑layer assemblies, while the smooth, low‑profile button head maintains a clean, finished appearance in exposed or clearance‑restricted applications. Featuring an internal hex drive for precise torque control, it is finished with a zinc‑baked coating and trivalent chromium (Cr+3) passivation to enhance corrosion resistance and reduce the risk of hydrogen embrittlement—making it well suited for industrial, automotive, and mechanical use.