M3/M4 304 stainless steel internal thread cylindrical pin double-pass positioning pin inner tooth fixing pin shaft pin hollow pin for Equipment Assembly

Our 304 Stainless Steel Internal Thread Cylindrical Pins (also known as Double-Pass Positioning Pins, Inner Tooth Fixing Pins, or Hollow Shaft Pins) are precision-engineered fasteners designed for secure positioning, alignment, and structural support in mechanical assemblies. Crafted from high-grade 304 stainless steel, these pins deliver exceptional corrosion resistance, rustproof properties, and high tensile strength, ensuring reliable performance in both indoor and outdoor environments—even in challenging conditions.

 

Featuring a unique internal thread design with a hollow cylindrical structure, these pins provide versatile fastening solutions for applications where traditional external thread fasteners are impractical. The double-pass (through-hole) threading allows for easy installation with a threaded rod or bolt, while the smooth cylindrical surface ensures precise alignment and tight fitting. The inner tooth design enhances grip stability, preventing loosening under vibration or heavy loads and ensuring long-term structural integrity.

 

Available in M3 and M4 common sizes, these hollow fixing pins are compatible with a wide range of mechanical components, making them ideal for diverse industrial applications. They are widely used in machinery manufacturing, mold assembly, equipment maintenance, automotive parts, electronic device casing, and precision instrument positioning—providing reliable support and alignment for critical components.

 

Engineered for durability and ease of installation, our 304 stainless steel internal thread cylindrical pins are suitable for professional engineers, machinery manufacturers, maintenance technicians, and hardware suppliers. They are also available for wholesale bulk orders, catering to the needs of industrial production lines, repair shops, and component suppliers—combining precision engineering, superior material quality, and versatile functionality in every fastener.