Apparatus for handling sample tubes, comprising: - a sample tube tray, - a sample tube individualizer, - a first conveyor, - a second conveyor, - a sample tube buffer, - a sample tube rack inserter, wherein - the sample tube tray is adapted to store sample tubes in bulk commodity, - the sample tube individualizer is adapted to sequentially unload single sample tubes from the sample tube tray and to sequentially provide the unloaded sample tubes to the first conveyor, - the first conveyor is adapted to convey the sample tubes to the sample tube buffer, wherein the sample tubes are closed by means of caps, wherein the sample tubes are provided to the first conveyer such that the sample tubes are initially conveyed in a random conveying direction, the random conveying direction being either cap first or cap last, - the sample tube buffer is adapted to buffer the sample tubes provided by the first conveyor and to provide buffered sample tubes to the second conveyor with a predeterminable, especially constant, sample tube rate, - the second conveyor is adapted to convey the sample tubes to the sample tube rack inserter, and - the sample tube rack inserter is adapted to insert the sample tubes into a sample tube rack said apparatus further comprising - a conveying direction determiner, adapted to determine the conveying direction of a respective sample tube, and - a conveying direction changer functionally coupled to the conveying direction determiner and the first conveyor, wherein the conveying direction changer is adapted to change the conveying direction such that each sample tube is provided to the sample tube buffer in a defined conveying direction, said apparatus being further characterized in that - the first conveyor comprises a first and a second belt (11, 12), the first and the second belt (11, 12) extending in parallel along a conveying direction and being spaced by a given belt distance, and in that - the conveying direction changer comprises a rotatable leg, the leg being arranged between the first and the second belt (11, 12), the leg having a width smaller than the given belt distance, and the leg when rotating changing the conveying direction of a sample tube placed on top of the leg. - a sample tube tray, - a sample tube individualizer, - a first conveyor, - a second conveyor, - a sample tube buffer, - a sample tube rack inserter, wherein - the sample tube tray is adapted to store sample tubes in bulk commodity, - the sample tube individualizer is adapted to sequentially unload single sample tubes from the sample tube tray and to sequentially provide the unloaded sample tubes to the first conveyor, - the first conveyor is adapted to convey the sample tubes to the sample tube buffer, wherein the sample tubes are closed by means of caps, wherein the sample tubes are provided to the first conveyer such that the sample tubes are initially conveyed in a random conveying direction, the random conveying direction being either cap first or cap last, - the sample tube buffer is adapted to buffer the sample tubes provided by the first conveyor and to provide buffered sample tubes to the second conveyor with a predeterminable, especially constant, sample tube rate, - the second conveyor is adapted to convey the sample tubes to the sample tube rack inserter, and - the sample tube rack inserter is adapted to insert the sample tubes into a sample tube rack said apparatus further comprising - the sample tube tray is adapted to store sample tubes in bulk commodity, - the sample tube individualizer is adapted to sequentially unload single sample tubes from the sample tube tray and to sequentially provide the unloaded sample tubes to the first conveyor, - the first conveyor is adapted to convey the sample tubes to the sample tube buffer, wherein the sample tubes are closed by means of caps, wherein the sample tubes are provided to the first conveyer such that the sample tubes are initially conveyed in a random conveying direction, the random conveying direction being either cap first or cap last, - the sample tube buffer is adapted to buffer the sample tubes provided by the first conveyor and to provide buffered sample tubes to the second conveyor with a predeterminable, especially constant, sample tube rate, - the second conveyor is adapted to convey the sample tubes to the sample tube rack inserter, and - the sample tube rack inserter is adapted to insert the sample tubes into a sample tube rack said apparatus further comprising - a conveying direction determiner, adapted to determine the conveying direction of a respective sample tube, and - a conveying direction changer functionally coupled to the conveying direction determiner and the first conveyor, wherein the conveying direction changer is adapted to change the conveying direction such that each sample tube is provided to the sample tube buffer in a defined conveying direction, - the first conveyor comprises a first and a second belt (11, 12), the first and the second belt (11, 12) extending in parallel along a conveying direction and being spaced by a given belt distance, - the conveying direction changer comprises a rotatable leg, the leg being arranged between the first and the second belt (11, 12), the leg having a width smaller than the given belt distance, and the leg when rotating changing the conveying direction of a sample tube placed on top of the leg.