A standard bearing unit (1) for different exhaust-gas turbocharger designs (8), having a shaft (2); having a shaft nut (18); having sealing devices (14, 15); having a compressor wheel (3) which is arranged on a first end (4) of the shaft (2); and having a turbine wheel (5) which is arranged on a second end (6) of the shaft (2), wherein the shaft (2) is mounted in a standardized bearing sleeve (7) which has predefined, unchangeable outer dimensions (19, 23) which are independent of the exhaust-gas turbocharger embodiment.