Special big collar hinge pin with internal threads

a) External hexalobular socket (6 lobe) / metric thread / self tapping thread for thermoplastics.

b) A double-end stud with collar is a type of fastener that features threaded ends on both sides and a non-threaded central collar or flange. Thread types of both sides can be customized according to customer's request, differen surface treatment is available upon request. 

This is a specialized fastener designed for specific applications where the screw needs to be tightened to a specific torque. 

a.) A taper pin is a cylindrical fastener made of steel that tapers uniformly from one end to the other, with one end having a slightly larger diameter than the other.

b.) This gradual taper allows the pin to fit tightly into a tapered hole, creating a secure, frictional hold without the need for additional fasteners or adhesives.

a.) A knurled head screw with internal threads inside the hole and grooves around the head is a specialized fastener designed for applications requiring manual tightening or where a secure grip is needed.

b.) The knurled head features textured grooves around its circumference, providing enhanced grip for hand-tightening or loosening. Meanwhile, the internal threads inside the hole enable the screw to be securely fastened to a threaded component or inserted into a pre-threaded hole.

A special double threaded screw with shoulder is a fastener designed with two distinct threaded sections and an integrated shoulder for precise positioning and alignment.

a.) It is a type of fastener that features a cylindrical-shaped head and an integrated collar or flange beneath the head.

b.) The flange serves multiple functions, including providing a larger bearing surface, distributing load more evenly, and enhancing the bolt's stability when installed.