A camshaft adjuster (2) having a locking cover (1) formed of sheet metal, wherein the locking cover (1) has a substantially disc-shaped base surface (3) and has a collar (7), which extends in an axial direction (5) and which runs at least partially around the base surface (3), for receiving a spring cover (31). As a result of the production of the locking cover (1) from sheet metal in combination with a turned-up collar (7), the locking cover (1) can be produced simply and cost-effectively and nevertheless offers adequately high strength despite the low material thickness.