A stud pin configured to be installed in a stud pin installation hole in a tread portion of a pneumatic tire includes a tip end which makes contact with a road surface; and a buried base embedded in the tread portion; pressure from the side surface of the stud pin installation hole on the bottom portion and the trunk portion securing the stud pin. The buried base extends in one direction and includes a flanged trunk portion provided between the bottom portion and the tip portion. The bottom portion includes a plurality of first recesses formed on and along an outer peripheral surface thereof that is in contact with a side surface of the stud pin installation hole. The trunk portion includes a plurality of second recesses formed on and along an outer peripheral surface thereof that is in contact with the side surface of the stud pin installation hole.

A stud pin and a pneumatic tire are provided. A tip portion of the stud pin includes an end surface with a concave polygonal profile shape including one recessed portion and one protrusion portion on a side opposite the recessed portion. The stud pin is mounted in a stud pin installation hole with the protrusion portion facing a leading side in a tire circumferential direction and the recessed portion face a trailing side.

A stud pin (30) arranged in a hole (24) in a tread portion of the pneumatic tire (1), includes: a first flange portion (31) having a first surface that faces the bottom surface of the hole and a second surface that faces in the opposite direction to the first surface; a body (34) connected to the second surface of the first flange portion, and that is arranged in the hole; a tip (35) supported by the body, and that projects to the outer side from the ground contact surface of the tread portion; and a through hole (40) that connects a first opening provided in the first surface and a second opening.

According to a first aspect of the present disclosure, there is provided a stud (100) for a pneumatic tyre. The stud includes a sleeve (120), which comprises or is formed of a thermoplastic elastomer or silicone based material and which comprises a pin hole (126). The stud also includes a pin (110) being formed as a unitary piece form a wear resistant material or compound and inserted into the pin hole (126).