Abstract: A linear motion device has a first assembly and a second assembly which is linearly movable relative to the first assembly, in which at least one first rolling surface which extends in a longitudinal direction is provided on the first assembly and is situated opposite a second rolling surface provided on the second assembly, and in which a row of rolling elements is located between the first and second rolling surfaces, and in which the first assembly includes a single-pieced, first body and at least one return assembly which may be installed as a whole, a return passage being provided in the first body, and furthermore in which at least one curved deflection passage is located entirely within the deflection assembly and connects the first rolling surface to the return passage in a manner such that the rolling elements may circulate endlessly, and in which at least one projection that engages in the return passage is provided on the deflection assembly.