a linking device has a bearing and is suitable for use with a weapons system . the device provides adjustable rotational resisting torque of two coaxial cylindrical parts which are rotatable relative to one another about a shared axis . the bearing includes two rings made of a resiliently deformable material and is capable of respectively engaging with the two cylindrical portions , and between which rolling elements are arranged such as to be in contact with raceways of said rings . the device further includes a controllable member for adjusting the tightening of the rings , wherein the controllable member is capable of engaging one of said parts in order to engage with said bearing .