A male-threaded rod end, commonly called a rose joint or heim joint, in the POS series with a 20 mm bore. The spherical ball allows the joint to articulate through a range of angles while carrying load along the rod axis, which is exactly what a suspension link, panhard rod, gear linkage or steering intermediate rod needs. The male thread screws into a tapped tube or clevis, and the assembly is normally locked with a jam nut once the length is set, giving you fine adjustment of geometry without disassembly. Check the mating thread and the bolt size that passes through the 20 mm bore before ordering, and inspect rod ends regularly on anything used on the road.