Functioning - The UX with rim is suitable for pre-positioned installation the UX without rim is suitable for push-through installation. - Turning in the screw causes the UX to expand in the solid building material and to knot within the cavity. - The required screw length is given by the plug length + fixture thickness + 1 x screw diameter. - Suitable for wood and chipboard screws, as well as stud screws. - In the case of board building materials, the threadless part of the screw must not be longer than the fixture, and the UX with rim is to be used. - The edge distance must be at least one plug length.