BELT TIGHTENER

A belt retractor () of a seatbelt system comprises a belt tensioner () which is adapted to rotate a belt reel () of the belt retractor () accommodated in a belt retractor frame (), wherein the belt retractor frame () is closed by a cover () on the tensioner side in the area of the spindle of the belt reel () and in the cover () a bearing for the belt reel () is provided. The cover () includes a first pot-shaped cover part () which is mounted directly on the belt retractor frame () and has a side wall () merging into a flat portion (). In the flat portion () an opening () is spared and a second cover part () is provided which engages in the opening () in the first cover part () and on which a bearing () is formed in which an end () of the spindle of the belt reel () is supported.