Overview
ISO 965-1 is a thread tolerance standard for ISO metric screw threads used in industrial, mechanical, and engineering fastening systems. It defines tolerance classes, tolerance positions, and fit requirements for internal and external metric threads to support reliable assembly performance. The standard is commonly referenced together with dimensional, mechanical property, coating, and inspection standards depending on the application requirements. ISO 965-1 is widely applied to bolts, screws, nuts, studs, threaded rods, and other threaded fastening components. When sourcing threaded components to ISO 965-1, additional specifications may include thread pitch, tolerance class, material grade, coating system, and certification requirements.