A pin connector includes: a metal outer shell having a tubular wall that has an inner surface, an annular shoulder face that is formed on the inner surface, and a punched rib that protrudes inwardly from the inner surface above the annular shoulder face; and a metal clamping device having an annular wall with an outer surface abutted against the inner surface, a retaining flange, and a plurality of resilient clamp arms. The retaining flange protrudes outwardly from the outer surface of the annular wall to extend over the annular shoulder face and is pressed by the punched rib against the annular shoulder face.