Abstract: A device for the production of a locking or braking effect between two elements, such as a shaft (20) and a hub (21), which display two concentric, cylindrical surfaces, which device includes a sleeve, made in one piece, for axial insertion between the surfaces. The sleeve is circumferentially divided into sleeve sections, which are separated by, at least partially, axially directed rows of holes in the body wall of the sleeve, and which are connected to each other by bridges, formed of the remaining wall material between the holes in the said rows. The body wall is provided with weak zones, designed to, through compression, project radially inwards and outwards into engagement with the said surfaces in order to achieve the locking and braking effect.