Grade 12.9 American imperial set screws are precision-engineered for heavy-duty positioning and locking applications, featuring a hex drive, headless design, and stop functionality. Available in key UNC thread sizes 2#-4#-40 and 6#-32, these screws deliver exceptional tensile strength (≥1200MPa) and torque resistance, making them ideal for securing shafts, gears, pulleys, and other machinery components in industrial equipment.
Crafted from heat-treated alloy steel, the 12.9-grade construction ensures superior durability, wear resistance, and stability—even in high-stress, vibration-prone environments. The headless design enables a low-profile, flush installation that eliminates interference with rotating or moving parts, preserving equipment functionality. The hex drive allows for easy, precise tightening with standard hex tools, enhancing operational efficiency, while the UNC coarse threads provide tight, reliable engagement with compatible American imperial components. As stop screws, they excel at limiting component movement and maintaining precise positioning in critical assemblies.
Core Features & Advantages
12.9-Grade Ultra-High Strength: Heat-treated alloy steel offers tensile strength ≥1200MPa, withstanding heavy loads and frequent vibration.
UNC American Imperial Threads: 2#-4#-40UNC and 6#-32UNC sizes ensure compatibility with standard American imperial components for tight engagement.
Hex Drive Headless Design: Enables flush, low-profile installation and easy tightening with standard hex tools, avoiding equipment interference.
