Abstract: Invention relates to a pin for clamping a sleeve 1 moulded from rubber and having a crenellated cut, of which the teeth 7 and spaces 8 match one another, so that the sleeve can be closed over a tube to be protected, the said sleeve being of the type with an embedded metal carcass 6 and terminating with a loop 13 in each tooth 7.The pin 10 which makes it possible to clamp the sleeve by penetrating all the loops of the carcass is of a type with a trapezoidal shank and is characterized in that the point of its shank has a gland 22, and in that the edges of the shank on and at the rear of the gland are rounded and polished.The invention can be used particularly for clamping protectors serving for drilling or production in an underground deposit.