Coaxial RF connector system (100, 200) comprising a coaxial RF connector and a coaxial RF counter connector, the coaxial RF connector comprising at least an inner conductor defining a center axis of the connector, an outer conductor coaxial to the inner conductor, and a first centering device (170, 130) at the outer conductor, the first centering device (170, 130) having an outer contour coaxial to the inner conductor, the coaxial RF counter connector comprising at least a counter connector inner conductor, a counter connector outer conductor coaxial to the counter connector inner conductor, and a second centering device (270, 230) at the outer conductor, the second centering device (270, 230) having an inner contour coaxial to the counter connector inner conductor, and when mated, the inner conductor and the counter connector inner conductor providing a galvanic contact with each other, and further the outer conductor and the counter connector outer conductor providing a galvanic contact with each other, wherein the first centering device has an outer size smaller than the inner size of the second centering device (270,230) or the first centering device has an outer size larger than the inner size of the second centering device (270, 230), and the first centering device matches to the second centering device (270, 230), characterized in, that the first centering device is electrically insulated from the RF connector outer conductor, and/or the second centering device (270, 230) is electrically insulated from the RF counter connector outer conductor, or an insulating sleeve or an insulating layer is included between the first centering device and the second centering device (270, 230). the coaxial RF connector comprising at least an inner conductor defining a center axis of the connector, an outer conductor coaxial to the inner conductor, and a first centering device (170, 130) at the outer conductor, the first centering device (170, 130) having an outer contour coaxial to the inner conductor, the coaxial RF counter connector comprising at least a counter connector inner conductor, a counter connector outer conductor coaxial to the counter connector inner conductor, and a second centering device (270, 230) at the outer conductor, the second centering device (270, 230) having an inner contour coaxial to the counter connector inner conductor, and when mated, the inner conductor and the counter connector inner conductor providing a galvanic contact with each other, and further the outer conductor and the counter connector outer conductor providing a galvanic contact with each other, wherein the first centering device has an outer size smaller than the inner size of the second centering device (270,230) or the first centering device has an outer size larger than the inner size of the second centering device (270, 230), and the first centering device matches to the second centering device (270, 230), characterized in, that the first centering device is electrically insulated from the RF connector outer conductor, and/or the second centering device (270, 230) is electrically insulated from the RF counter connector outer conductor, or an insulating sleeve or an insulating layer is included between the first centering device and the second centering device (270, 230).